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study programme
Original title in Czech: Pokročilé materiály a nanovědyFaculty: CEITECAbbreviation: CEITEC-AMN-CZ-PAcad. year: 2023/2024
Type of study programme: Doctoral
Study programme code: P0588D110002
Degree awarded: Ph.D.
Language of instruction: Czech
Accreditation: 26.4.2021 - 26.4.2031
Mode of study
Full-time study
Standard study length
4 years
Programme supervisor
prof. RNDr. Radim Chmelík, Ph.D.
Doctoral Board
Chairman :prof. RNDr. Radim Chmelík, Ph.D.Vice-chairman :prof. Ing. Radimír Vrba, CSc.Councillor internal :prof. RNDr. Josef Jančář, CSc.prof. RNDr. Tomáš Šikola, CSc.doc. Ing. Miroslav Kolíbal, Ph.D.prof. RNDr. Karel Maca, Dr.Councillor external :prof. RNDr. Ludvík Kunz, CSc.prof. RNDr. Václav Holý, CSc.prof. RNDr. Jiří Pinkas, Ph.D.
Fields of education
Issued topics of Doctoral Study Program
This doctoral topic will study the properties of metal/metal, metal/ceramic, and polymer/ceramic interpenetrating phase composites with broad range of application including bone repair. The aim is to explore additive manufacturing to control the fraction, topology, and consequently, the properties of the new composites. The research involves the design of new composite topologies, additive manufacturing and consolidation of the composites, characterization of the structure and the mechanical performance, and explore numerical models to predict the mechanical response. Along the studies, the candidate will have the opportunity to learn and work from the synthesis to the characterization of the materials. Highly motivated and collaborative candidates with outstanding track of records and with the ambition to learn from both materials and biological sciences are welcome to submit an application.
Tutor: Montufar Jimenez Edgar Benjamin, M.Sc., Ph.D.
This doctoral topic explores material extrusion and vat polymerization for the additive manufacturing of titanium porous structures with applications such as tissue engineering scaffolds, bone implants and catalytic supports. The research involves the development of new titanium formulations for use in additive manufacturing, topology optimization, sintering and characterization of the mechanical, chemical and biological performance. Along the studies, the candidate will have the opportunity to learn and work from the synthesis to the characterization of the materials. Highly motivated and collaborative candidates with outstanding track of records and with the ambition to learn from both materials and biological sciences are welcome to submit an application.
Laser-induced plasmas are fundamental for countless applications, e.g., material characterization using laser-induced breakdown spectroscopy (LIBS). Laser-matter interaction and plasma properties in LIBS experiments under various ambient conditions are still not fully understood. The aim of this thesis is to do extensive research in the field of morphology and properties of laser-induced plasmas generated under various ambient, as well as under extraterrestrial conditions. The partial aim of the present Ph.D. project is to decouple the plasma characterization from the optical emission spectra and consequently obtain more robust information about the laser-induced plasma’s properties (such as homogeneity, temperature, electron number density, and the presence of local thermal equilibria). This will be done using temporally and spatially resolved imaging, scattering (e.g., Thomson scattering), absorption, and interferometric techniques. Using information obtained via these techniques, the plasma parameters will be determined independently from the optical emission spectra and the calibration-free approaches will be improved.
Tutor: Pořízka Pavel, doc. Ing., Ph.D.
Organisms, which can cause very serious diseases, are traditionally classified among important pathogens, and their early detection is crucial for possible treatment. To determine these substances, immunochemical methods with nanoparticle labeling are used. However, in this research area, the development of new imaging techniques is also necessary. In recent years, methods based on laser ablation have proved to be very promising, nevertheless, their optimization is still necessary.
Although lead-free textured BCZT ceramics exhibit promising piezoelectric properties, the piezoelectric response of these materials still suffers from high scatter due to difficulties in processing textured microstructures. Due to powder synthesis and processing limitations, it has not been possible to correlate piezoelectric properties with different structural parameters and optimize the textured microstructure. In this research project, newly developed advanced ceramic processes will be adapted to the BCZT system and combined with the template grain growth method to achieve textured high-density tapes with excellent piezoelectric performance. For a better understanding of the effect of grain structure on material properties, the samples will be thoroughly characterized in terms of mechanical, microstructural, dielectric, and piezoelectric behaviour.
Tutor: Trunec Martin, prof. Ing., Dr.
Multifunctional advanced ceramic materials exhibit a proper synergy of mechanical, optical, electrical or magnetic properties. The processing of such materials requires the optimization of all steps of the ceramic technology, i.e. the treatment of the input powder precursors and the selection of suitable methods of their shaping and sintering. The aim of the dissertation work will be the utilization of modern ceramic technology methods (dry and wet forming methods, pressure-less and pressure-assisted sintering) to prepare multifunctional ceramic materials and composites and evaluate their microstructure and properties in relation to possible applications. Within the ongoing Horizon Europe project "GlaCerHub" (co-ordinator K. Maca), it will be possible to complete Cotutelle studies (double-degree-type studies) in cooperation with the University of Trenčín. During the course of the study, the specific topic of the work will be specified in cooperation with the student and the FunGlass Center of Excellence Trenčín (e. g. High-Enthropy Ceramics with luminescent properties, Transparent ceramics with luminescent properties, etc.).
Tutor: Maca Karel, prof. RNDr., Dr.
X-ray inspection is widely used for non-destructive analysis of internal structure of castings, workpieces or assemblies. It primarily search for the presence of pores, cracks, material defects or parts position. The position of the specimen during scanning plays one of the most important roles in radiography and also computed tomography for reliable defect detection. The dimensions and shape of the part, the image artifacts of the scanning system, and the nature of the defects must be taken into account during scanning. For this purpose, it is essential to design a proper scanning strategy and to be able to adjust the position of the sample directly in the X-ray system. With the availability of simulation software for the acquisition process, knowledge of standards, advanced image processing methods and robotic arms as feeders, these challenges can be overcome. This topic aims to explore new possibilities and design a reliable X-ray inspection aproach both methodologically and instrumentally.
Tutor: Zikmund Tomáš, doc. Ing., Ph.D.
The project is focused on the study of antibacterial and antiviral properties of nanostructured surfaces and/or parylene coatings. Various technological approaches to the synthesis of nanowires from metals and oxides with an antimicrobial effect will be used. The production of a composite film from parylene and antimicrobial nanoparticles will also be addressed, or post-modification of parylene with antimicrobial molecules. In addition, the project will include the production and characterization of a parylene film with micro/nano hierarchical structures, which will also be tested against bacteria and viruses.
Tutor: Fohlerová Zdenka, doc. Mgr., Ph.D.
X-ray computed tomography (CT) is one of the most powerful methods for 3D visualization and inspection. This non-destructive method especially provides sufficient resolution and contrast to evaluate any microstructural features, with the ability to resolve structures even below one micron. The complete information about any biological sample, from macroscale to nanoscale, can be then easily acquired in non-destructive manner and thus enabling the visualization and the quantification of cellular features and intracellular spaces opening the way for virtual histology, live cell and subcellular imaging and correlative microscopy. This work addresses the practical implementation of lab-based CT systems with high-resolution for imaging and mainly 3D characterization of biological structures by development of dedicated sample preparation and CT measurement methodologies together with testing and evaluation of possibilities of advanced CT techniques such as phase-contrast imaging CT or dual-energy CT for those applications.
Recent advances in x-ray detection technologies have opened new possibilities in the field of computed tomography. Direct conversion systems make it possible to localize the detected photons more accurately. Devices with this technology also exhibit a direct relationship between the energy of incident photons and the magnitude of the output signal. Furthermore, cutting-edge photon counting technology enables modern detectors to discriminate between individual incident photons and measure their energies precisely. All these technologies can be used for high-speed acquisition with low noise, high-resolution spectral imaging, and quantitative tomographic methods. However, the novelty of these detectors also necessitates further research and development in terms of their applications. The aim of this topic is to study the suitability of these advanced technologies in the fields of metrology and industrial tomography, which focus on dimensional accuracy and require detectors to be calibrated according to widely recognized and norms and standards.
As a part of this doctoral thesis, micro-electromechanical systems (MEMS) devices will be fabricated by a combination of electron beam lithography (EBL) and deep etching procedures enabling high degree of accuracy and control. The devices will be focused on sensors, actuators and microfluidic cells, e.g. pressure, tension, and flow sensors. The devices will be operationally tested and simultaneously or separately characterized by advanced analytical techniques: scanning probe microscopy (SPM), scanning electron microscopy (SEM), Raman spectroscopy and transport measurements. Devices will be specified with regard to projects solved in cooperation with the company Thermo Fisher Scientific and related to their contribution in the field of basic research and their publication impact.
Tutor: Bartošík Miroslav, doc. Ing., Ph.D.
This work will be focused on application of expanded graphite (EG) in rubber matrix with the aim to modify mechanical and electrical properties of prepared vulcanizates. Morphology, interaction of EG with the rubber matrix, electrical properties (conductivity, electromagnetic shielding), rheological, tribological and mechanical properties will be investigated. Existing theoretical models will be used for describing mechanical and electrical properties of EG composites such as Young’s modulus and conductivity, respectively.
Tutor: Kučera František, Mgr., Ph.D.
Quantum computers are currently applied in an ever-growing number of scientific and engineering research areas. Their onset is foreseen also in theoretical calculations in computational materials science. The prime topic of this PhD study will be to use currently available quantum computers and their simulations in a theoretical study of materials. The secondary topic will be to develop a suitable software tools for applications in the case of quantum computing technologies and systems.
Tutor: Friák Martin, Mgr., Ph.D.
In this project, the PhD candidate will study applications shaped beams in electron microscopy and spectroscopy. The student will focus on fast and damage-free imaging and spectroscopy, probing low-energy excitations beyond the usual selection rules and studying optical dichroism, everything down to the atomic scale.
Tutor: Konečná Andrea, doc. Ing., Ph.D.
Address accurate reconstruction of image background and cell segmentation using artificial intelligence. Quantitative phase imaging has specific requirements, and standard approaches developed for fluorescence or other light microscopy contrast techniques are not directly applicable. Artificial intelligence will be useful in decomposing the image, and corrected raw data will be finally used to ensure maximum accuracy of the phase measurements.
Tutor: Zicha Daniel, Ing., CSc.
X-ray imaging offers a way to non-destructively visualize the internal structure of the measured sample. It is often used to determine the presence and morphology of defects (inclusions, pores, cracks, etc.) in samples across many industries. Artificial intelligence, and specifically deep learning, currently represent stat- of-the-art in various image analysis tasks, including the detection of defects. However, the problem of limited or low-quality ground-truth annotated data often arises. In this project, advanced training strategies and weakly supervised, or completely unsupervised techniques will be developed to create robust deep learning models for defect detection in industrial X-ray imaging. These models will finally be validated on a multitude of real applications of X-ray imaging-based defect detection.
Tutor: Kaiser Jozef, prof. Ing., Ph.D.
The highly-engineerable scattering properties of metallic and high-index semiconductor/dielectric nanostructures currently underpin the operation of nowadays metasurfaces. They support geometrical plasmonic or Mie resonances that offer strong light-matter interaction and excellent control over the scattering phase and amplitude. Their optical responses tend to be of a simple, linear form and they are hard to modify with external stimuli. As a result, basic Maxwell equation solvers can be used to predict and optimize their behavior. In stark contrast, van der Waals (vdW) materials comprised of atomically-thin layers bonded by the vdW force exhibit a fascinating diversity of quantum, collective, topological, non-linear, and ultrafast behaviors. It is exciting to think how such materials may open up new functions for metasurfaces [1]. This PhD topic aims to start addressing that question by exploring the new fundamental physics that can emerge at the cross roads of the metasurface and vdW fields. We will start by exploring how the properties of two-dimensional (2D) vdW semiconductors materials, such as the transition metal dichalcogenides (TMDCs), can be modified by subwavelength patterning to form atomically-thin metasurfaces. Further, flat 2D-material based metasurface optical devices for dynamic wavefront control providing new functionalities not achievable by bulk optical elements or “classical” plasmonic or all-dielectric metasurfaces will be studied. References: [1] J. van de Groep et al., Exciton resonance tuning of an atomically thin lens, Nature Photonics 14, 426–430 (2020).
Tutor: Šikola Tomáš, prof. RNDr., CSc.
Proposed doctoral thesis will be focused on the research in the field of biodegradable polymeric materials based on thermoplastic starch, polymeric blends with TPS and composites of TPS reinforced with cost-effective nature materials derived from food industry as by-products. The aim is the optimization of the composition of TPS/biodegradable matrice-filler system with respect to mechanical properties, processability, biodegradability, hydrophobic/hydrophilic behaviour etc. Rheological analysis will be the key tool for the optimization of the polymeric blends with optimal material properties suitable for conventional plastics processing technology and testing for application in single use disposable products according to CZ and EU legislation.
Use of biopolymers in functional materials with structurally programmable properties is needed. Here, focus is on block multi-oligo-saccharide (BMOS) networks with the structurally programmed swelling behavior. Native and waste polysaccharides are enzymatically degraded into oligosaccharide precursors and functionalized for solubility and connectivity to form a library of coding building blocks. Swelling behavior of BMOS networks is structurally programmed by linking sequence of building blocks into chains with encoded solubility and designing type, density and spatial organization of inter-chain X-links. Processing and materials design concepts are developed in the form toolbox consisting of library of code elements with different hydrophilicity and programing algorithms linking them into sequence enabling structurally program desired swelling behavior. BMOS networks with programmable swelling behavior can restore soil water holding capacity, enable effective plant disease control, simplify plant breeding and support effective use of food and agricultural waste. The primary goal is a library of block co-oligosaccharides with hydrophilicity coded by the sequence of their monodisperse blocks and utilization of the library for programming kinetics of the water uptake and release in the cross-linked block co-oligomer networks.
Tutor: Jančář Josef, prof. RNDr., CSc.
The knowledge of electron spin relaxations is of crucial importance for development and improvement of spintronic devices, catalytical processes as well as in nuclear magnetic resonance (NMR) sensitivity enhancement method, so-called dynamic nuclear polarization (DNP) technique. In this regards the PhD student will implement pulsed Electron Spin Resonance (ESR) methods to the existing high-end Frequency Rapid Scan (FRASCAN) ESR spectrometer at CEITEC, which is operating up to frequencies 1 THz, magnetic fields 16 T, and temperatures down to 2 K. The goal of this PhD topic can be divided into two parts. Firstly, the student will implement high-frequency pulsed ESR technique into the existing FRASCAN spectrometer by developing new (Fabry-Perot resonator) and adapting existing sample holders supporting multi-frequency tunning for measurements of various samples in liquid and solid phases. Focus will be given on resonant frequencies at 263 GHz, 329 GHz, 394 GHz and 459 GHz, which are of importance for DNP studies. Secondly, the successful implementation of above will allow performing multi-frequency T1 and T2 spin relaxation studies of organic radicals as well as thin films deposited on Fabry-Perot resonator mirrors in wide range of frequencies and temperatures. These relaxation studies will be further correlated by those obtained by frequency rapid scan experiments performed in the group. In summary, the student will be well trained in cutting edge magnetic resonance method developments in one of the worldwide leading groups.
Tutor: Neugebauer Petr, doc. Dr. Ing., Ph.D.
Candidate will be trained in catalytic conversion of CO2 to value added products, 3D printing, 2D materials synthesis, characterization and modification. Candidate will learn how to use different technologies of 3D printing to achieve desired electrocatalyst design. He/she will learn how to prepare high performance devices. Supervisor, Prof. Pumera, is highly cited researcher, see www.pumera.org, more info about the group on www.energy.ceitec.cz PhD candidate will be trained to use high end equipment at nano.ceitec.cz
Tutor: Pumera Martin, prof. RNDr., Ph.D.
The contact resistance between organic semiconductors (OS) and the electrode is one of the main limiting factors that hinder the applicability of OS, for example, in organic field-effect transistors. Our research shows that this problem can be overcome by embedding a thermally tunable charge injection layer (CIL) composed of aromatic carboxylic acids into the interface. However, the influence of such CILs on the interface properties, including energy level alignment, interfacial charge transfer, or subsequent molecular growth, is not well understood yet. The Ph.D. candidate will perform ab-initio calculations to investigate the structural and electronic properties of Charge Injection Layers, describe their impact on subsequent molecular layers, and design new molecular precursors for CILs to enhance their performance. Calculations will be performed within the framework of density functional theory using state-of-the-art first-principles codes (VASP, SIESTA, FHI-aims). The data will subsequently be used for accurate electronic structure calculations and effective structural predictions employing machine learning. The acquired results will be thoroughly analyzed and compared with the experiment performed in the host group. The studies are supported by a running project. For more information, please, contact Jan Čechal or Jakub Planer.
Tutor: Čechal Jan, prof. Ing., Ph.D.
III-nitrides (Ga,Al,In-N) are direct wide-bandgap semiconductors in which atoms are held together by ionic and covalent forces. We have recently developed an empirical model for GaN with self-consistent charge transfer, which treats ionicity at the same footing with covalency. The objective of this project is to utilize this new model to investigate the structures and charge transfer around extended defects in GaN and AlN using the methods of molecular statics and dynamics. In the second part of the project, this method will be applied to study interfaces between hexagonal AlN and Si{111} as well as between cubic GaN and Si{100}. New knowledge from these simulations will be immediately correlated with another project currently running in the group, which focuses on optimization of the early stage of epitaxial growth of III-nitride films.
Tutor: Gröger Roman, doc. Ing., Ph.D. et Ph.D.
Proposed PhD project is oriented on the synthesis and characterization of magnetically active transition metal and/or lanthanide complexes showing specific magnetic phenomena like spin crossover effect, single molecule magnetism or single chain magnetism. Such coordination compounds exhibit magnetic bi- or multistability and in this sense are very attractive from the application point of view. Possible technological utilization might be in the case of high capacity memory devices, display technologies, spinotronics, contrast agents for magnetic resonance imaging etc. PhD study will be focused on the advanced organic and coordination synthesis of mononuclear and polynuclear complexes of transition metals and/or lanthanides. New-prepared compounds will be characterized by analytical and spectral methods and magnetic properties will be studied by means MPMS SQUID.
Rotationally symmetric electromagnetic lenses used for imaging in electron microscopy are burdened by imaging aberrations that limit their resolution. Several physical principles have been described in the literature, which make it possible to correct aberrations of electromagnetic lenses. Image correction can be achieved, for example, by a multi-pole electromagnetic field, a phase plate formed by a solid substance or field, an electrostatic mirror and others. Correction systems have been successfully implemented on some types of electron microscopes (e.g. a hexapole corrector for a spherical aberration in a transmission microscope). The dissertation will be focused on the methodology of correction of imaging aberrations and the design of a correction system for an electron microscope in cooperation with the company TESCAN.
Tutor: Zlámal Jakub, Ing., Ph.D.
X-ray computed tomography (CT) is an important method for 3D non-destructive imaging of samples in many fields. It is commonly used in industry for defect detection and quality control, scientific projects utilise imaging and quantification of data and apply a number of analyses to determine morphological and physical parameters. To put CT data in context with other methods, they often have to be supplemented with established imaging methods such as electron and light microscopy and qualitative techniques such as X-ray spectroscopy. The data from each technique typically have a different format, size, resolution, etc. Combining such different information about samples is a challenge. When correlating two different 3D datasets, it is necessary to ensure that the sample structures correspond to each other. For a combination of 2D and 3D techniques, a corresponding 2D section has to be found in the 3D dataset. This requires a programming approach or a use of special software. The work will deal with techniques of correlation of information from various imaging methods. Such a multidisciplinary approach is in high demand today and has a big potential.
Wide band gap materials are in the center of current technological advancement in power electronics, mostly due to recently developed fabrication techniques of bulk crystals. Most importantly, SiC and GaN have started to question silicon use in certain applications. However, compared to silicon, current know-how of relevant properties of these materials is not mature enough. Student will focus on analysis of defects in SiC and GaN by correlative micro- and spectroscopies. A part of the work is a realization of proof-of-concept device in electronics/optoelectronics. A necessary prerequisite is solid knowledge of solid state physics and principles of relevant spectroscopic techniques. The research will be conducted in collaboration with Thermo Fisher Scientific or Onsemi. Students are strongly advised to contact the supervisor before the official admission interview.
Tutor: Kolíbal Miroslav, doc. Ing., Ph.D.
Properties of multifunctional magnetic materials are closely linked to the subtle interplay of different order parameters. The thesis aims at combining electron diffraction techniques with different depth sensitivity to investigate the relation between structural and magnetic order in complex materials. The project assumes previous practical experience with electron microscopy.
Tutor: Uhlíř Vojtěch, Ing., Ph.D.
Engineering and production of novel materials, including coatings and layers, is demanding new analytical solutions. Compared to other analytical techniques, Laser-Induced Breakdown Spectroscopy (LIBS) enables selective ablation of layers with variable depth resolution. However, the depth of the analysis with certain number of laser pulses differs for individual materials. The calibration of depth to laser pulse number is also of an issue, while there is no solid evidence for this phenomenon in classical LIBS literature. The goal of this thesis is to find complementary approaches, for instance using Computed Tomography and standard approaches of metallography, in depth profiling in order to fully calibrate LIBS technique to depth profile analysis. As an output, methodological protocol applicable across broad range of materials is demanded.
The dissertation will focus on the design and fabrication of dielectric metasurfaces for unconventional optical elements in the ultraviolet, visible, and infrared wavelength regions. Specific metasurface design methods using optimization algorithms with multiparametric metrics, such as the Gerchberg-Saxton algorithm, will be explored. Fabrication approaches, including electron beam lithography, dry etching, and various deposition techniques for preparing dielectric layers, will also be investigated. Additionally, simulations of individual metasurface building blocks will be an integral part of the research. The main goal of this work is to produce fully characterized prototypes of metasurfaces with verified functionalities, which could be used for shaping high-performance optical beams or in the transmission and processing of optical signals in communication technologies.
High surface-to-volume ratio of nanostructures makes them theoretically ideal candidates for applications in catalysis and storage of hydrogen. Strong catalytic effect of transitional elements was found in nanolayered Mg/Ti, Ti/Pd or Al in nanolayer material Ti/Mg/Ti/Pd and Mg-AlTi. Several interesting classes of materials have been already prepared but there is a lack of proper understanding of bonding in these nanostructures, which strongly affects the catalytic and sorption/desorption capacities of these materials. The objective of this project is to formulate a new computational framework for modeling these nanostructures, which will be based on the adiabatic shell model. The first step will be a formulation of this model for Mg-H, and the use of computer atomistic simulations to describe various forms of bulk hydrides and nanoparticles. This model will be subsequently extended to include transition elements such as Ti, Al or Pd to explore the catalytic properties of these nanoparticles as well as their capacity for storing hydrogen. The results of these simulations will provide guideline for the design of new nanostructured materials for catalysis and hydrogen storage at IPM ASCR.
Tutor: Ostapovets Andriy, Ph.D., Mgr.
The aim of the thesis will be the design of 3D nanostructured materials with the aid of the new method. The principle is a preparation of the 3D structures by stacking of very thin layers. The collection of the layers will create a 3D pattern that can show functional properties. These materials can be structured similarly to natural materials, for example, a cell membrane-like structure. Other materials may exhibit controlled release of active molecular compounds for medical applications such as capsaicin. The student's task will be to cooperate in the development of this method. Next, his/her task will be the designing of his/her own systems which can be created by this method. The topic is proposed in the framework of the TAR project and is in cooperation with the Vietnamese Academy of Sciences. (The student can but will not be obliged to travel to Vietnam, other international cooperation and travel will be also appreciated and supported.)
Tutor: Žídek Jan, Mgr., Ph.D.
Plastic materials are intensively polluting our environment. They are getting into the food chain and influencing individual bio-organisms in the form of microplastics. Their toxicity and impact on living organisms, thus, must be assessed. The topic of this thesis is to find an integrative approach to study the fate and effects of emerging microplastics in the aquatic environment. Main goal is to find methodology for analysis of microplastics accumulated in aquatic organisms in order to understand adverse outcomes.
Pulsed Electron Paramagnetic Resonance (EPR) methods are intensively used to investigated structure and dynamics of complex macromolecules containing unpaired electrons. Among these methods Pulsed Electron-Electron Double Resonance (PELDOR) also known as Double Electron-Electron Resonance (DEER) has emerged as a powerful technique to determine relative orientation and distance between macromolecular structural units on nanometre scale. For successful applications of pulsed EPR methods it is important to have tools enabling transformation of measured signals into structural information. The goal of this PhD project is to develop new effective computational procedures and computer programs for the processing of measured pulsed EPR data in order to extract structural and dynamical information from experiments. This goal also includes application of the developed computational methods to real experimental data obtained on the molecules tagged with spin labels. For more details please contact Petr Neugebauer.
The amount of data obtained in one experiment is steadily increasing. Contemporary state-of-the-art Laser-Induced Breakdown Spectroscopy system provide bulky data sets with millions of objects (spectra) and thousands of variables (wavelengths). Thus, there is a must driven by more efficient data storage, handling and processing; this might be tackled by lowering the dimension of raw data sets. This demands to truncate the information and omit redundancy and noise. In this work, advanced mathematical algorithms will be investigated, with special attention to non-linear algorithms. The main parameter is robustness of the algorithm. Outcomes of this thesis will be directly applied to data processing in various applications, including the multivariate mapping of sample surface.
Dual-energy computed tomography (DECT) is a modality that was formerly used only at synchrotron-based facilities. Recently it has been used in medical sphere of computed tomography (CT) and nowadays potential of DECT has been tested on lab-based CT system with high resolution. This technique uses two energetically different X-ray spectra for examination and specific differentiation of individual sample components, in terms of materials or tissues, based on their attenuation properties. This differentiation is feasible even for materials which would be inseparable in CT data from standard CT measurement using only one beam energy. Therefore, an advantage of DECT is a possibility of precise material segmentation and classification. Furthermore, acquired information from DECT measurement can be utilized for creating pseudo-monochromatic CT images which results in specific reduction of tomographic artifacts e.g. beam hardening. Aim of this thesis will be study of DECT technique and testing its potential and utilization in sphere of laboratory CT system with submicron spatial resolution.
The theoretical analysis of novel optical effects and functionalities in modern nanophotonic structures is impossible without adequate and powerful numerical tools. Interestingly, the methods based on eigenmode expansion (EME), enabling a deep physical understanding of the problem, are often overlooked. That is why the project will focus on development and application of EME techniques suitable for the study of selected interesting problems of contemporary nanophotonics. Application will address topics such as nanophotonic lattices that support bound states in the continuum, the issues related with the loss compensation in plasmonic structures, systems with gain and loss where realistic models of gain media based on the rate equations for the populations is used, and modulation in hybrid waveguides with graphene.
Tutor: Petráček Jiří, prof. RNDr., Dr.
Implementation of antiferromagnetic materials in spintronic devices would allow increasing the operation speeds up to the Terahertz range and scaling down the device size to nanometer scale due to the absence of magnetic stray fields. The thesis will focus on exploring the fundamental physical mechanisms to control antiferromagnetic configurations using electrical current. The relevant phenomena are related to spin-orbit torques created by the spin Hall effect, alternatively to antiferromagnetic domain fragmentation using electrical current or optical pulses. The model platforms would involve antiferromagntetic and ferrimagnetic materials.
The project is focused on the fabrication of fibers from polyvinylidene fluoride (PVDF), an attractive material for making functional scaffolds, via electro-spin coating method. The choice of PVDF is due to an excellent piezoelectricity and good biocompatibility. Electrospun PVDF scaffolds can produce electrical charges during mechanical deformation, which can provide necessary stimulation for repairing tissue. The candidate will work on the fabrication of scaffolds with randomly oriented or uniaxially aligned fibers. The scaffolds will be characterized using various methods such as SEM, XPS, FTIR, XRD, contact angle. The main part of the project will focus on determining the piezoelectric properties of PVDF fibers and their potential contribution in the use of these piezoactive materials in liquid environments and as part of hydrogel structures. In addition, the biological characterizations of scaffolds including viability assays and the detection of parameters demonstrating electromechanical activation of cells will be performed. c
Candidate will be trained in ammonia conversion, 3D printing, 2D materials synthesis, characterization and modification. Candidate will learn how to use different technologies of 3D printing to achieve desired electrocatalyst design. He/she will learn how to prepare high performance devices. Supervisor, Prof. Pumera, is highly cited researcher, see www.pumera.org, more info about the group on www.energy.ceitec.cz PhD candidate will be trained to use high end equipment at nano.ceitec.cz
Electron sources used in electron microscopes generate a beam with an energy distribution whose width is characteristic of the given source. The low energy dispersion is advantageous for microscopic techniques, because especially at low accelerating voltage, the contribution of the chromatic aberration is a significant factor limiting the resolution. The aim of the dissertation will be the design of an energy filter for the electron beam, which will enable the narrowing of the energy distribution in the electron beam emitted from the Schottky source and its realization in cooperation with the TESCAN company.
Ultra Fast TEM (U-TEM) allows to monitor dynamic phenomena such as phase changes, melting/crystallization of materials with time resolution in ns to ps. Furthermore, samples sensitive to electron beam exposure can be observed using stroboscopic illumination (another U-TEM mode). Current U-TEM microscopes use photoemission sources or a combination of standard sources with very fast deflectors (RF cavity,…). Nanostructured materials appear to be very promising for the production of U-TEM electron sources. For example, GaN materials are seems to be good candidate for this purpose due to their considerable chemical and thermal resistence, low switching voltage of 1.25 V/um and high current density. The properties of the cathode depend to a large extent on the shape and form of nanostructures such as nanotubes, nanocarbons and nanocrystals.
The PhD study will be aimed at characterization of van der Waals materials and measurement of their functional properties. It will especially cover new types of these materials such as MXenes, their multilayers with TMDs, as well as 2D perovskites. As the major investigation tool, electron microscopy will be applied, namely a newly developed 4D STEM with FIB for fabrication and in situ analysis of lamellas of these materials, as well as HR (S)TEM for getting atomically resolved information. This will enable to study structure (electron diffraction), composition (EDS, EELS) and selected functional properties (e.g. localized surface plasmons and their coupling with excitons) of these novel materials.
The dissertation will deal with the development of electron tweezers, which allows to move droplets of eutectic liquids on the surface of semiconductors. The electron tweezers utilize the focused electron beam and is already tested in the UHV-SEM microscope, developed in cooperation with TESCAN company. During the controlled movement, the gold-containing droplet can for example etch or otherwise modify the surface of semiconductors (germanium, silicon). The dissertation thesis should focus on the interaction of different eutectic droplets with various substrates including 2D materials (graphene, etc.). Part of this work will be optimization of this process including its real-time monitoring using UHV-SEM microscope.
Tutor: Bábor Petr, Ing., Ph.D.
The topic of the Ph.D. thesis is focused on the experimental description of La-Ni-M ternary systems in the entire concentration range at different temperatures. These alloys are perspective materials for the formation of the hydrides and their potential use in the field of hydrogen storage materials. The storage of hydrogen in the solid phase has a high application potential in the field of power supply and transport. Alloy samples will be prepared using a arc melting furnace and subsequently annealed for a long time in quartz glass ampoules. The prepared samples will be characterized using a combination of static and dynamic analytical methods, mainly scanning electron microscopy SEM, X-ray powder diffraction XRD and thermal analysis DSC/DTA. Based on the obtained data, an experimental ternary phase diagram will then be constructed. A powder will be created from the selected samples and their reactivity with hydrogen will be tested and the kinetics of hydrogen adsorption and desorption will be studied. The aim of the theoretical part of the thesis is the modeling of phase equilibria and phase diagrams using the CALPHAD (Calculation of Phase Diagrams) method implemented in Pandat and ThermoCalc programs. The result of the theoretical part of the work will be a predicted phase diagram with the best possible agreement with the obtained experimental and the data from literature.
Tutor: Zobač Ondřej, Mgr., Ph.D.
The development of this topic aims to manufacture porous metallic materials using the direct foaming method. The project involves the surface modification, study of the microstructure and mechanical properties of the materials, as well as their cytocompatibility. At the end of the Ph.D. program, the applicant will have skills and conceptual knowledge of the manufacture and characterization of porous materials with application in industry and biomedicine. Applicants must demonstrate initiative and disposition for research, with a solid professional, methodological and ethical training, to develop original research.
Tutor: Oliver Urrutia Carolina, MDDr., Ph.D.
Additive manufacturing offers an effective option of design and rapid prototyping for diverse industry branches. It is expected that these techniques will find applications in small- to medium-scale production in the case of critical components with high production and service demands. Generally, additive manufacturing opens novel and revolutionary production opportunities in terms of shape complexity, previously impossible to achieve by conventional manufacturing processing. One of the most frequently used techniques of additive manufacturing is selective laser melting which utilizes powder feedstock, which is locally melted by the controlled movement of a laser beam. The melting and subsequent solidification results in the fabrication of a structure with the desired shape. Recently, several studies explored the possibility to control the solidification process by laser scanning parameters optimization with the aim to control the crystallographic orientation of microstructure. This approach opens the novel and interesting options for the industry – the fabrication of complex components with tailored microstructure with respect to expected service loading. The topic of PhD thesis will be focused on optimization of selective laser melting parameters to obtain materials with certain microstructure and subsequent characterization of the effect of various crystallographic orientation on fatigue behaviour and fatigue performance. The student will cooperate tightly on SLM processing parameters optimization with the research staff of the NETME centre. Furthermore, the student will adopt deep user knowledge of scanning electron microscopy (SEM) which will be intensively used for the characterization of fabricated microstructures. Fatigue tests will be carried out by modern Instron and MTS testing machines. Obtained results will be analysed with relation to the findings of thorough characterization of deformation mechanisms detected by optic and electron microscopy. The results will contribute to a deeper understanding of fatigue resistance of SLM-processed steels. Objectives of the thesis: 1. Selective laser melting optimization with the aim to obtain structures with strong anisotropy in prominent crystallographic directions. 2. Comprehensive characterization of cyclic stress-strain response. 3. Fatigue performance description of particular structures with respect to a given type of anisotropy. 4. Analysis of active deformation mechanisms and characterization of typical processes related to fatigue damage.
Tutor: Šmíd Miroslav, Ing., Ph.D.
3D printing represents an additive manufacturing method with an unprecedented control over the shape of the printed body and its internal structure. One of the shortcomings of the simple FDM techniques is inability to print cellular solids without the use of a secondary supporting material. Auxetic materials are porous structures characterized by the negative Poisson´s ratio. 3D printing enables fabrication of cellular structures with gradient of porosity as well as gradient of Poisson´s ratio, resulting in metamaterials with unprecedent mechanical properties. Frantal polymerization is a novel polymerization technique enabling low energy in-situ polymerization of various monomers within any cellular structure. The project will investigate auxetic structures printed using light initiated epoxy matrix systems including their complex mechanical and thermomechanical response. It will also involve characterization of the morphology, reaction kinetic assessment with FTIR, photo-DSC, and photo-rheology, mechanical and thermomechanical measurements with DMA.
The PhD project will concentrate on a study of complex issues related to development of UV detectors using GaN (Ga)/graphene nanostructures. The initial part of the study will focuses on the preparation of Ga and GaN nanostructures on poly-and single-crystal graphene using a low-temperature deposition method. The low temperature growth of GaN nanocrystals will be carried out by a combination of UHV PVD technologies such as Ga vapour deposition and low energy nitrogen ion-beam (50 eV) post-nitridation using a unique ion-atomic beam source [1] . The growth of GaN will be realized at much lower temperatures (T<250°C) than in conventional technologies (e.g. MOCVD, 1000°C). Subsequently, the relation between parameters/functional properties of Ga and GaN nanostructures and deposition conditions will be studied. The complex characterization of the Ga (GaN)/graphene nanostructures will be provided by Scanning Electron Microscopy (SEM), Scanning Probe Microscopy (AFM, EFM, SKFM), Raman spectroscopy, photoluminescence micro-spectroscopy, etc. Finally, the electrical response of the nanostructures to UV radiation will be studied via a FET-setup utilizing these optimized nanostructures as photosensitive elements. References: [1] J. Mach, P. Procházka, M. Bartošík, D. Nezval, J. Piastek, J. Hulva, V. Švarc, M. Konečný, and T. Šikola, Nanotechnology, Vol. 28, N. 41 (2017).
Spin waves in the THz region have become a subject of growing interest due to a high group velocity of magnons (steep dispersion curve) which renders them attractive for the design of ultrafast spintronic devices [1]. Here, antiferromagnetic materials like rare earth orthoferrites (RFeO3) could be a solution because of their very high (terahertz) frequencies of spin resonances [2], [3]. However, due to the lack of efficient sources and detectors, the physics of magnons at THz frequencies is far less studied. The proposed interdisciplinary PhD study combining photonics and magnetism is based on generation and detection of THz spin waves by near fields enhanced by plasmonic resonant structures - antennas. It brings a new qualitative view into this subject. The antennas will be fabricated on a substrate surface, ideally on ribbons or magnonic crystals made out of RFeO3 thin film samples (e.g. TmFeO3) by EBL/FIB at CEITEC. Then, the magnons propagating along these structures will be analysed by a Brillouin light scattering (BLS) micro-spectrophotometer [4], using the method reported in [5] and successfully implemented at CEITEC [6]. Further, to extend the detected Brillouin-zone range, plasmonic resonant nanostructures providing large momentum components in their near-field hot spots will be used as well [7]. In this PhD study, plasmonic resonant structures for generation and detection of magnons should be optimized, and then dispersion relations tuned by shape, dimensions and periodicity of ribbons/magnonic crystals [6] and external magnetic field. Supportively, magnetic near-field enhanced THz T-D spectroscopy might be applied to test magnon-polariton dispersion curves of the thin film samples according to [3]. References: [44] K. Zakeri, PHYSICA C 549, 164, 2018. [45] J. Guo, J. Phys.: Condens. Matter 32, 185401, 2020. [41] K. Grishunin, ACS Photonics 5, 1375, 2018. [46] T. Sebastian, …, H. Schultheiss, Front. Phys. 3, 35, 2015. [47] K. Vogt, …, B. Hillebrands, Appl. Phys. Lett. 95, 182508, 2009. [38] L. Flajšman, …, M. Urbánek, Phys. Rev. B 101, 014436, 2020. [X] R. Freeman,,…., Phys. Rev. Research 2, 033427 (2020).
Generative models are machine learning models that are used to learn a probability distribution of the data. When the underlying distribution is correctly captured, it can be easily sampled to obtain new data or compute (physical) quantities. Recently, many novel architectures appeared (e.g. for text-to-image generation) with exceptional performances. Accordingly, there are many scientific applications ranging from cosmology to condensed matter systems. We will explore the potential of these models for spectroscopic data. The focus will be laid on so-called energy-based models that take inspiration from physics.
Graphene-based variable barrier interface transistors present a promising concept for organic semiconductor devices with several advantages, i.e., high driving current, high-speed operation, flexibility, and scalability while being less demanding for lithography. However, this research requires a multilevel experimental approach, as the substrate determines the growth of the first layers, which, in turn, influences the growth of thin films. The goal of the Ph.D. is to describe and optimize the growth of organic semiconductors on graphene from the mono- to multilayers. The Ph. D. study's experimental research within the Ph.D. study aims to understand the kinetics deposition/self-assembly phenomena of organic molecular semiconductors as a function of temperature, flux, and graphene doping. We will employ a range of complementary techniques including low energy electron microscopy, X-ray and ultraviolet photoelectron spectroscopy and scanning tunneling microscopy, all integrated in a single complex ultrahigh vacuum system. The Studies are supported by a running project. (For detailed information, please, directly contact Jan Čechal)
Laser powder bed fusion (L-PBF) technology has emerged as a game-changer that holds great promise for producing complex component geometries with complicated internal structures that are difficult to produce with conventional technologies. Student will focus on Ni- based superalloy IN939 produced by L-PBF. Special attention will be paid to the effect of building direction and heat treatment (HT) on microstructure and related fatigue and creep behavior. Description of complex high-temperature degradation mechanisms operating during fatigue and creep loading of HT L-PBF IN939 will be provided using advanced microscopy techniques. Experimental data on fatigue and creep behavior together with intense microstructural scrutiny and numerical modeling will pave the way to an improved understanding of high-temperature degradation mechanisms of L-PBF Ni-based superalloys
Tutor: Kuběna Ivo, Ing., Ph.D.
Hydrogen is a very prospective and eco-friendly fuel which can bring significant economical and environmental benefits. The main obstacle that impedes expected future of hydrogen technology is safe and acceptably efficient hydrogen storage (HS). It is generally accepted that a possible solution to this problem is HS in solid phase of metallic materials (HSM). However, there are not HSMs up to now with sufficient HS properties at low temperature and pressure. Therefore, the main idea of this study is to investigate HS properties of new perspective model alloys which could show effective HS at temperatures near to room temperature and at low pressure. One of ways how to influence HS properties HSM is to change their phase and chemical composition. The results could lead to new strategies in development of HSM.
Tutor: Král Lubomír, Ing., Ph.D.
Hydrogen is a very prospective and eco-friendly fuel which can bring significant economical and environmental benefits. The main obstacle that impedes expected future of hydrogen technology is safe and efficient hydrogen storage (HS). It is generally accepted that a possible solution to this problem is HS in solid phase of metallic materials (HSM). However, there are not HSMs with sufficient HS properties at low temperature and pressure. Therefore, decreasing the thermodynamic stability of hydride phase of HSM with high hydrogen capacity is crucial for tuning their HS properties. One of ways how to influence thermodynamic properties is changing of structure states and chemical composition of HSM. The main idea of this study is to investigate the HS properties of model Mg-alloys in various states of structure from critically cooled or amorphous state to ordered crystallized structure. These materials could show desired HS properties at lower temperatures and pressures. The results could indicate new ways for development of new HSM.
The Low Energy Ion Scattering (LEIS) has proved its capability to study composition of the solid-state surfaces. It is a low energy modification of the famous experiment of Rutherford with scattering of alpha particles on gold foil. The extreme surface sensitivity of the technique is widely used in analysis of the elemental composition of a topmost atomic layer with nanometre depth resolution. The sensitivity of the methods originates mainly from charge exchange mechanisms between the projectile and involved surface atoms. Only a small fraction of the scattered projectiles leaves the surface in ionized state. This ion fraction is represented by characteristic velocity that is the measure of the charge exchange processes and is characteristic to the given combination of projectile and surface atom. The characteristic velocity is frequently influenced by chemical arrangement of the sample surface as well. This project aims to the characterisation of the charge exchange processes between the He and Ne ions (projectiles) on variety of solid-state surface and thin layers. The primary kinetic energies of the projectiles will be varied within the range between 0.5 keV to 7.0 keV. Outputs of the project will significantly improve the potential of the LEIS technique at the field of quantitative analysis. The experiments will be performed on dedicated high sensitivity LEIS instrument – Qtac100 (ION TOF GmbH) at Ceitec BUT and at partner institutions (TU Wien, Imperial College London and Twente University. See for example: Highly Sensitive Detection of Surface and Intercalated Impurities in Graphene by LEIS. (By S. Prusa and H.H. Brongersma), https://pubs.acs.org/doi/10.1021/acs.langmuir.5b01935.
Tutor: Průša Stanislav, doc. Ing., Ph.D.
Nanoparticles and nanoparticle systems have a unique position among nanomaterials. They have many important applications in technologies, biology, and medicine, and a huge potential for future developments. The physical and chemical properties of nanoparticles (nanometric volumes of materials) are fundamentally influenced by their morphology. Decreasing the particle size enlarges the surface-to-volume ratio, which can be utilized in chemical reactions (chemical catalysis), and to tune physical properties of these materials (quantum dots, superparamagnetic and magnetic nanoparticles). The topic of this dissertation is the structural and phase characterizations of nanoparticles and their aggregates using electron microscopy. The experimental results will help to unravel the relationship between their properties and structure, and will be used to optimize their synthesis method and functionalization.
Tutor: Pizúrová Naděžda, RNDr., Ph.D.
Geometric-phase optical elements are a new tool for complex light shaping and generation of special states of light. Unlike traditional refractive elements, the geometric-phase elements control the light using transformation of its polarization state. Thanks to technology of liquid crystals or principles of plasmonics, geometric-phase elements provide abrupt phase changes on physically thin substrates. Compact size and unique polarization properties make them ideal candidates for simply integrable spatial light modulators. The dissertation thesis topic is to find and verify the potential of geometric-phase elements in common-path digital holography and advanced optical imaging.
Tutor: Bouchal Petr, Ing., Ph.D.
Laser-Induced Breakdown Spectroscopy (LIBS) is a powerful analytical technique that has been gaining popularity in the polymer industry for the detection and quantification of trace elements. One challenge in the analysis of polymer matrices is the detection of halogens and other elements at trace levels. Multi-pulse LIBS has been shown to improve the detection limits of halogens and other trace elements in polymer matrices. The main aim of this thesis is the use of multi-pulse LIBS for the detection of trace elements (esp. halogens) in polymer matrix. This approach should offer several advantages over other analytical techniques; it requires minimal sample preparation of a variety of polymers, including polyethylene, polypropylene, and polyvinyl chloride. This technique has the potential to improve the quality control of polymers by providing accurate and reliable detection of trace elements, which can affect the performance and properties of the final product.
The work will focus on determining the structure-design-properties relationship of nickel-based superalloys as an ever-progressive material. The topic of the work will be to characterize the influence of casting defects and structural notches representing stress concentrators on the fatigue life of engineering components. In particular, the relationship between the microstructure of the superalloy and its tolerance to defects during cyclic loading at elevated temperatures will be monitored. Fatigue tests will be performed on samples without and with structural notches. While scanning electron microscopy will be used for structural analysis and determination of the effect of structural defects, transmission microscopy will be used for deeper analysis of operating mechanisms of fatigue damage. The results of the work will extend knowledge about the influence of defects on the fatigue life of nickel-based superalloy components and help predict their fatigue life.
Tutor: Fintová Stanislava, doc. Ing., Ph.D.
This thesis will focus on the assessment of the effects of surface treatment by the LSP method on various types of alloys. Laser shock peening (LSP) cures the surface using a pulsed laser beam, which generates a strong compression shock wave upon impact with the surface of the material. The shock wave propagates through the material and creates compressive residual stresses on the surface of the material. This increases the resistance of the material to certain defects or increases the hardness of the surface layer. Various microscopic methods, X-ray diffraction and other methods will be used to characterize the material.
There is growing interest in understanding magnetism of materials combined with 2-dimensional materials such as graphene. In particular, the impact of magnetic materials intercalated between the 2D material and its supporting substrate has the potential for magnetic ordering and may lead to modification/control of magnetic properties. Additionally, a system of magnetic material + 2D material could potentially be monolithically integrated with other devices to create new, robust electronic functionalities. The objective of this project it to develop and carry out strategies of intercalating magnetic atoms and molecules using graphene or other 2D materials. The subsequent structures would then be characterized by a wide range of surface probes as well as high field and frequency electron spin spectroscopy and nuclear magnetic resonance techniques. The knowledge gained will then be used to develop predictive models of magnetism for the intercalant + 2D material/substrate. This work will be carried out in collaboration with the US Naval Research Laboratory and will have opportunities for on-site research.
Magnetism emerges in matter due to the presence of unpaired electronic spins and the interaction between them in a wide range of materials from oxides to molecular materials. The collective behavior of spins, also known as quantum entanglement of spins, is a very active area of research with application to communication and computation. Electron spin resonance (ESR) is a key technique that enables to investigate spin states and spin-spin interactions. It has been successfully applied to monomeric and dimeric spin systems for identifying quantum transitions between entangled phases by varying parameters such as the temperature or the orientation of an external applied magnetic field. The aim of this project is to identify suitable materials such as spin dimers of molecular nature and apply ESR spectroscopy to study quantum phase transitions in the high frequency (up to 1 THz) and high field (up to 16 T) regime.
Laser ablation of matter is an essential process involved in the chemical analysis using various techniques of analytical chemistry. The spectroscopic investigation of characteristic plasma emission provides qualitative and quantitative information about the sample of interest. Standard analysis is based on the processing of emission signal; the process of laser ablation and consecutive development of laser-induced plasma is marginal and of little analytical interest. But, understanding the complexity of laser-matter interaction is a crucial step in the improvement of the latter data processing approaches. Thus, this work will target the investigation of spatial and temporal development of laser-induced plasmas, imaging of plasma plumes and determination of their thermodynamic properties. Outcomes of this work will be used in further advancement of the ablation of various materials (incl. biological tissues), improvement of optomechanical instrumentation (collection optics) and optimization of signal standardization.
Plastic recycling and production is currently at its climax, current legislative is forcing faster processing of material while avoiding toxic metal content. Plastic industry is looking for solution in analytical chemistry, with high throughput and satisfactory analytical performance. Laser-induced breakdown spectroscopy (LIBS) technique is being intensively applied in various industrial applications. Its robustness and instrumental simplicity drive its direct implementation into production processes and even to production lines. The goal of this thesis is design of LiBS instrumentation, methodological protocol for classification of individual plastic materials and detection of toxic metals using LIBS spectra.
Laser-Induced Breakdown Spectroscopy (LIBS) is getting established in various industrial applications. This method excels for its instrumental simplicity and robustness and is thus a potential alternative for existing techniques. When considering LIBS as an analytical tool, it is necessary to evaluate its analytical performance and the level of implementation into the existing production line. The topic of this thesis is the identification of individual industrial applications and the development and adaptation of analytical apparatus together with the optimization of measurement methodology from sample pretreatment to data processing.
The topic aims at optimizing quantitative analysis of cell behavior with high accuracy for measurements of cell reactions to experimental treatments with applications in cancer research. The topic involves cell culture, specimen preparation for microscopy, time-lapse acquisition, image processing, data analysis, and interpretation. Requirements: knowledge of fundamentals of optics, cell biology, microscopy, coding, the ability to work independently and in a team, and high motivation.
The PhD project is aimed at the study of strong coupling between the localized surface plasmons in antennas and phonons in resonantly absorbing non-metallic environments and, consequently, to exploitation of this knowledge for finding and utilizing general principles of spatially localized plasmon-enhanced absorption. The study will tackle this issue in the near IR and mid-IR range and verify it in new types of uncooled antenna-coupled microbolometers with improved sensitivity and spatial resolution response. Due to common characteristics of index of refraction at absorption peaks/bands of materials, the outcomes and conclusions can find direct applications in other spectral regions, regardless the physical origin of resonant absorption. It will make it possible to carry out research on challenging phenomena exploitable not only in the local heating of materials, but also in IR and light detection, energy harvesting, (bio)sensing, quantum technology, etc. References: Břínek L. et al., ACS Photonics 5 (11), 4378-4385, 2018
Single molecular magnets (SMM) are molecular entities bearing nonzero magnetic moment. In addition to the magnetic properties SMM provide one important attribute: they represent two-state system that can be in superposition state, i.e., SMM represent quantum bits (qubits). Recent developments pushed the coherence properties of individual magnets to the range required for competitive qubits. However, for any future application the molecular qubits should be processable as thin films. Moreover, the individual qubits should be mutually interacting. The goal of PhD study is to prepare long-range ordered arrays of molecular qubits on solid surfaces a possible basis for a molecular quantum registry. The experimental research within the PhD study aims at the understanding of deposition/self-assembly phenomena of organic compounds containing magnetic atoms on metallic and graphene surfaces. A special focus will be given to graphene surfaces that provide means to control their electronic properties (by intercalation or external gate voltage) and, hence, mutual interaction of individual spins. The spin coherence properties will be investigated by cooperating partners at CEITEC and University of Stuttgart. (For detailed information, please, directly contact the Jan Čechal)
Switchable systems based on metal complexes able to change magnetic properties are highly attractive for sensor applications, new electronic devices, or active smart surfaces usable in materials providing high-density data storage. For these applications, the magnetic activity of metal complexes can be utilized and furthermore, it can be modulated by modification of their coordination, redox, electronic and ligand field properties. Three ways to obtain such function are to vary the ligand field strength, switching the coordination chemistry or switching the degree of coupling between two spin metal ions in the case of polynuclear compounds. The aim of the project is to synthesize bi- or multistable metal complexes incorporating switch regulation site in order to perform controlled spin change. Our systems will be characterized by different physical techniques: high field and frequency EPR and NMR spectroscopy, Mass spectrometry, SQUID and X-Ray crystallography.
There are numerous uses for electron paramagnetic resonance (EPR) spectroscopy in chemistry, physics, biology, materials science, and medicine. EPR has a less adopted use in applied sciences compared to nuclear magnetic resonance (NMR), partly because the interpretation and analytical work for comprehending the results of a set of observations require a spectroscopist with a dedicated background in the technique. This PhD project will use contemporary machine learning (ML) algorithms to automatize spectral analysis using computer-simulated spectra as a training set and prove the concepts by applying them to real data obtained in the lab. This will help bring the powerful features of EPR as a characterization and diagnostic technique closer to other communities inside and outside the academic sphere by creating an automatized tool for spectral analysis. The extensive range of EPR experiments makes it impractical or even impossible to cover all modes and applications. Thus, the student will concentrate on the spin trapping method, which uses continuous-wave EPR to identify radical species in catalytic reactions. There is a vast online database for assigning radical species with their EPR-derived spectrum parameters, and the assignment process will also be automatized. Upon the success in this application, the workflow can be adapted to be used in different spectral fitting problems. Objectives - Review the literature and understand the theory and applications of EPR spectroscopy. - Identify the range of all relevant EPR parameters for the common spin trapping agents, adducts and develop an algorithm to create the training set for the ML algorithm. - Select and train a ML algorithm with one, two and possibly more adduct species with a variable concentration in order to automatize the fitting of experimental data. - Use the online database (https://tools.niehs.nih.gov/stdb/index.cfm) to enable the automatic identification of radical species based on the results of the fitting. - Develop a tool with a user interface to make the solution available to the community via open repositories. - Prepare manuscripts with described and discussed results to be submitted to peer-reviewed journals. Keywords: Electron Paramagnetic Rezonance (EPR), machine learning (ML), spin trapping, radical, catalysis. Literature: [1] WEIL, John A. a James R. BOLTON. Electron paramagnetic resonance: elementary theory and practical applications. 2nd edition. Hoboken: Wiley-Interscience, 2007. ISBN 978-0-471-75496-1. [2] Jeschke, G. (2019). Quo vadis EPR? Journal of Magnetic Resonance, 306, 36–41. https://doi.org/10.1016/J.JMR.2019.07.008 [3] Biller, J. R., & McPeak, J. E. (2021). EPR Everywhere. Applied Magnetic Resonance 2021 52:8, 52(8), 1113–1139. https://doi.org/10.1007/S00723-020-01304-Z [4] Roessler, M. M., Salvadori, E. (2018). Principles and applications of EPR spectroscopy in the chemical sciences. Chemical Society Reviews, 47(8), 2534–2553. https://doi.org/10.1039/C6CS00565A
Machine learning is a novel and promising method to model interatomic interactions in a computationally efficient way. One of the research areas potentially suitable for application of such a method is the research of grain boundaries, particularly their strengthening or embrittlement due to segregated impurities. This PhD topic will cover generation and DFT (density functional theory) benchmarking of machine-learned potentials, their subsequent application to large-scale models of grain boundaries and testing their transferability.
Tutor: Černý Miroslav, prof. Mgr., Ph.D.
Localized surface plasmons (LSP) generated in metal nanoparticles (plasmonic antennas) can exhibit various modes differing in energy, charge distribution (dipoles vs. multipoles) and radiation capability (bright and dark modes). One of the most effective methods enabling generation and characterization - mapping of these modes at the single antenna level is Electron Energy Loss Spectroscopy (EELS) provided by High-resolution Scanning Transmission Electron Microscopy (HR STEM). The PhD study will be aimed at application of HR STEM-EELS for mapping the modes of LSP in plasmonic antennas. The emphasis will be especially put at a study of hybridized modes of coupled antenna structures and/or strong coupling effects between modes in plasmonic antennas and excitations in their surrounding environments. These excitations will be polaritons in quantum nanodots localized nearby antennas (the visible range) and/or phonons in absorbing antenna substrate membranes (IR – mid IR). In the former case, the experiment will be carried out by HR STEM-EELS at CEITEC Nano infrastructure (Titan), in the latter case, by Nion Ultra STEM available at some laboratories abroad (e.g. Oak Ridge national laboratory).
Superparamagnetic nanoparticles of Fe3O4 (magnetite) are utilized as active ingredients in treating cancer by the process of magnetic hyperthermia. Under alternating magnetic fields above 100 kHz the magnetic moments of individual nanoparticles reorient by the applied field. This results in opening the hysteresis loop whose area is proportional to the heat transferred into the surrounding tumor. These nanoparticles are being synthesized and optimized in our group for use in environments of different viscosities, incl. characterization of their structural and magnetic properties. The objective of this work is to carry out detailed computer atomistic simulations of these nanoparticles to explain how their functional properties depend on their shape, size and surface treatment. They will be made using molecular statics and dynamics in LAMMPS using empirical potentials endowed with magnetism. The mechanism governing the reorientation of these spins upon the reversal of the magnetic field will be studied using the Nudged Elastic Band method. These studies will also provide the shape of the energy barrier that is required in the Monte Carlo studies of nanoparticle aggreggates.
Metal-insulator transition (MIT) is a phase change between high-conductivity and low-conductivity state of matter, typically related to strong electron-electron correlation. Materials exhibiting MIT are promising candidates for applications in fast optical switching or novel optical elements. While the mechanism of MIT is satisfactorily understood in bulk materials, much less is known about the role of domain boundaries, atomic-scale defects, or interfaces in nanostructures. Ph.D. thesis shall focus on utilizing temperature-dependent analytical electron microscopy to gain a deep insight into the interplay between temperature, local crystal structure, and electronic structure for MIT in a specific material, possibly vanadium dioxide.
Tutor: Křápek Vlastimil, doc. Mgr., Ph.D.
Periodic arrays of ferromagnetically coupled transition metal atoms on topological insulator surfaces are predicted to break time-reversal symmetry. This can result in the emergence of, e.g., a quantum anomalous Hall effect, leading to a wide range of interesting physical properties and potential applications, e.g., in spintronics and quantum devices. The goal of the Ph.D. is to prepare periodic arrays of magnetic atoms embedded in 2D metal-organic frameworks (MOF) on topological insulator substrates (Bi2Se3, Bi2Te3). The MONs will be prepared via self-assembly from molecular precursors and transition metal atoms. Their properties will be investigated by combining surface-sensitive UHV techniques (low energy electron microscopy and diffraction, scanning tunneling microscopy, and X-ray photoelectron spectroscopy) with frequency domain EPR and magneto-optical spectrometry. The goal is to realize the hybrid organic-inorganic material system, describe the growth kinetics to obtain large area MOFs, optimize their structure to display long-range ferromagnetic order, and tune the Fermi level position by additional adsorbate doping or intercalating. The studies are supported by a running project. (For detailed information, please, directly contact Jan Čechal)
Presence of internal interfaces is important for functional properties of bulk materials as well as for properties of nanoparticles. Interfaces can serve as barriers for dislocation glide or mediate plasticity by themselves. Besides, internal interfaces can affect shape and symmetry of nanoparticles. Twin boundaries are specific kind of interfaces, which have special symmetry and, as rule, low energy. Variety of twin modes are known for materials with non-cubic symmetry (Mg, Ti, Ni-Ti etc.), where twin boundaries can occur as consequence of plastic deformation, crystal growth or phase transformation. However, this process is often spontaneous and development of methods to control the process is important and still unsolved problem. This project is devoted to computer simulations of twinning process in order to develop methods how to reach of initiation and subsequent growth of specific type of twin in non-cubic metallic materials.
Candidate will construct microrobots powered by chemicals for environmental remediation using polymer and inorganic chemistry approach.
Fatigue crack growth is a process that is described macroscopically by quantities such as the stress intensity factor, J-integral or plastic part of the J-integral. There are many models of crack propagation at the microscopic level that consider plastic deformation around the crack tip, but which differ in details. Advances in experimental methods allow more accurate and detailed experimental study of these processes and, consequently, their more accurate description and modelling using advanced molecular statics and dynamics methods. The aim of this work will be to collect as much details as possible about the processes at the tip of a fatigue crack during its growth, both on the surface of the specimens and in their volume. Modern methods will be used: high-resolution digital image correlation (HR DIC), electron channelling contrast imaging (ECCI), high-resolution electron backscatter diffraction (HR EBSD), focused ion beam (FIB) to observe the processes on selected sections and to prepare TEM lamellae. The observations will be complemented by simulation of microscopic processes using molecular dynamics or discrete dislocation dynamics.
Tutor: Kruml Tomáš, prof. Mgr., CSc.
Auxetic materials are materials with a negative Poisson's ratio. Their specific feature is that, unlike standard materials, they expand in the perpendicular direction during tensile deformation. This factor gives a wide range of applications for highly stressed components, which should be fixed. Auxetic material cannot be easily removed from the place where it is fixed. Their disadvantage is low rigidity. One way for auxetic material reinforcement was when combined with a conventional porous material with a positive Poisson's ratio. The student will deal with various possibilities of combining materials with negative and positive Poisson's ratio. The effect of reinforcement and stress distribution during deformation will be investigated. Materials will be theoretically described using solid-phase mechanics.
For detailed info please contact the supervisor.
Tutor: Kalousek Radek, doc. Ing., Ph.D.
The aim of the work will be to describe the molecular motion of water in macromolecular systems by molecular dynamic simulations. Water in macromolecular systems usually moves in a random Brownian motion. Nevertheless, there exist materials, where motion of water molecules is directed. One molecular system with directed motion will be investigated. The student will investigate this system by the molecular dynamic simulations, and he/she will describe the mechanism of the directed motion. The student can design his/her model or choose one of the models that are currently investigated. The first example is a hydrogel in which motion is controlled by water groups fixed in space. It has been found that the combination of interacting groups with fixation in space causes better adsorption of water compared to the groups with motion. The aim of this study will be to discover the mechanism of increased adhesion. The second example is a phenomenon called durotaxis, where a drop of water moves on the surface of the material in the direction of stiffness gradient. Durotaxis on rigid surfaces is currently well described. The mechanism of durotaxis on soft surfaces is currently partly described. However, there is still a good area to describe all aspects of such a motion. The topic is investigated in cooperation with the Institute of Physics of the Polish Academy of Sciences in Warsaw.
Organic semiconductors (OS) have emerged as a promising alternative to traditional inorganic electronics, with applications in various devices such as OLEDs, OFETs, solar cells, memories, and sensors. Despite the extensive research on the bulk properties of OS layers, the performance of these devices is limited by the charge transfer through the metal electrode-OS interface. The goal of the Ph.D. is to address these limitations by combining the advantages of weakly and strongly interacting molecular systems through carboxylic acid molecular monolayers (MMLs) as tunable charge injection layers (CILs) at the metal electrode-OS interface. The controlled deprotonation of the COOH groups of the carboxylic acid molecules on silver substrates will enable tuning of the interaction strength, position of the aromatic core, and effective coupling between the metal and OS, leading to low contact resistance and improved device performance. The molecular system will be studied by a unique combination of surface science techniques employing mainly low energy electron microscopy (LEEM), scanning tunneling microscopy (STM), and X-ray photoelectron spectroscopy (XPS) under ultrahigh vacuum (UHV) conditions. (For detailed information, please, directly contact Jan Čechal or Pavel Procházka)
This work is focused on systematic experimental research of the connections between the surface topography of the substrate and the adhesion, microstructure, and useful properties of thermally sprayed coatings. The surface topography of the substrate will be characterized by multiscale analysis. As part of the work, conventional and advanced material systems for application in the areas of transport and energy production will be studied. The aim of the work is to identify the optimal topography of the substrate, which will lead to the improvement of the useful properties and the increase of the service life of the existing coatings.
Tutor: Slámečka Karel, Ing., Ph.D.
Prismatic dislocation loops in metals are created by radiation damage or by severe plastic deformation. These loops are then obstacles for dislocations needed for plastic deformation and the material becomes brittle. The prismatic dislocation loops will be studied by molecular dynamic modeling and also by experiments using transmission electron microscopy.
Tutor: Fikar Jan, Mgr., Ph.D.
The candidate will develop novel nanorobotic systems for cancer drug delivery. The following skills will be learned: nanorobots fabrication, propulsion systems, SEM, XPS, microscopic characterization. Work with biological systems.
The candidate will develop new nanorobotic systems to detect DNA mutations in organisms. He/she will master the following skills: nanorobot fabrication, propulsion systems, SEM, XPS, microscopic characterization. Work with biological systems.
The candidate will develop novel nanorobotic systems for the removal of biofilms from titanium implants. The following skills will be learned: nanorobots fabrication, propulsion systems, SEM, XPS, microscopic characterization. Work with biological systems.
The candidate will develop new nanorobotic systems for operation in space in microgravity. He/she will master the following skills: nanorobot fabrication, propulsion systems, SEM, XPS, microscopic characterization. Working with biological systems. Close collaboration with the European Space Agency.
There is a great interest in miniaturizing bioelectronic implant devices, such as those used for neurostimulation or drug delivery. The most important aspect is efficient wireless powering and data transfer. Most methods rely on electromagnetic induction, but this suffers from geometric constraints. Our alternative is using optical power/data transfer using LED light sources and photovoltaic receivers. This is enabled by using tissue-penetrating wavelength in the deep red and infrared part of the spectrum. This work will include experiments on powering biomedical implants, including with animal models. Computer modelling will also be used. This work is sponsored by the company Opto Biosystems Ltd. and close collaboration is envisioned, leading to clinical translation applications.
Tutor: Glowacki Eric Daniel, doc., Ph.D.
Due to their dimensions comparable with the wavelength of light, nanostructures can directly modify properties of reflected and/or transmitted electromagnetic waves. The discipline investigating the interaction of an electromagnetic wave and nanostructures is called Nanophotonics. Its applications can be found for instance in photovoltaics or enhanced optical spectroscopy. Besides the shape and dimensions of nanostructures, the light can be also modified by their material properties. Recently, many scientific teams have been concentrating on the optically active advanced materials such as perovskites or 2D transition metal dichalcogenides (TMDs). These advanced materials can be often characterized by their photoluminescence, especially using confocal optical spectroscopy, time-resolved spectroscopy, or scanning near-field optical microscopy. All these experimental techniques together with adequate numerical simulations (e.g., FDTD, DFT, BEM) are available at the Institute of Physical Engineering BUT and will constitute the main tools for successful completion of the PhD research project.
Magnetic materials constitute a highly tunable platform for the design of adaptive optical and magnonic elements. Moreover, coupled order parameters in complex magnetic phase-transition materials can be controlled using various driving forces such as temperature, magnetic and electric field, strain, spin-polarized currents and optical pulses. The Ph.D. candidate will explore the first-order metamagnetic phase transition in materials that have been subjected to strong spatial confinement and optical stimuli and design new functional systems by combining individual structures with well controlled properties into 2D and 3D arrays.
Bound states in the continuum (BICs) represent a theoretically interesting way of field localization, which contradicts the conventional wisdom of bound states with energies solely outside the continuum of free states. BICs offer a number of interesting applications; for example, in photonics, BICs enable development of sensitive nanostructures with significant reduction of radiation leakage [1,2]. The project will focus on theoretical analysis and physical understanding of the operation of photonic waveguide structures supporting the propagation of a selected type of BIC. We assume the design and subsequent systematic research of selected photonic waveguide structures that resemble a lattice investigated in Ref. 3 and support the so-called symmetry protected BIC. The student will perform simulations with the aim to confirm the existence of the assumed BICs. Subsequently, the behavior of BICs will be investigated, and structural parameters will be optimized in order to achieve the required properties. [1] K. Koshelev, A. Bogdanov, and Y. Kivshar, “Engineering with Bound States in the Continuum,” Opt. Photonics News, vol. 31, no. 1, p. 38, 2020 [2] S. I. Azzam and A. V. Kildishev, “Photonic Bound States in the Continuum: From Basics to Applications,” Adv. Opt. Mater., vol. 9, no. 1, pp. 16–24, 2021 [3] Y. Plotnik et al., “Experimental observation of optical bound states in the continuum,” Phys. Rev. Lett., vol. 107, no. 18, pp. 28–31, 2011
In this study plasmonic resonant nano-and micro-structures (particles, antennas, tips) will be used for enhancement of photoluminescence of nanostructures such as nanodots, nanowires and 2D materials (e.g. metal dichalcogenides: MoS2, WS2,....). In this way single photon sources provided by defects of these structures might be recognized.
Plasmonic antennas are conductive nanostructures allowing to enhance and concentrate light at the nanoscale. They often exploit the lightning-rod effect, a local enhancement of the electric field near sharply curved surfaces. Despite its importance in plasmonics, the effect is understood mostly intuitively: a comprehensive description of its fundamentals is missing. The thesis aims to provide such insight. Partial effects contributing to the overall lightning-rod effect will be investigated: plasmonic surface wave localization, the effect of the curvature, the effect of the charge reservoir, and the effect of plasmonic gap enhancement between two interacting plasmonic antennas. The methodology will be based on electromagnetic simulations and experimental techniques for the local field characterization. A detailed understanding of the lightning-rod effect will provide a guideline for the design of plasmonic antennas with particularly large field enhancement.
Transition metal-based compounds (TMC), such as MAX phases and ABO3-type perovskites, are promising candidate materials for environmental remediation uses and green energy production. Among other additive manufacturing technologies, robocasting offers a powerful and versatile tool to shape these materials into frameworks with controlled hierarchical microstructure, porosity, and chemistry, which have exceptional physical and chemical properties. This research is focused on the preparation of printable pastes based on transition metal (Ti, Fe, Ni…) compounds using different mechanochemical (high-energy ball milling, spray drying, etc.) and chemical methods (wet chemistry syntheses) or their combinations. The influence of various parameters of prepared pastes on the shaping and sintering behavior of framework structures from TMC, their functionalization, and the resulting catalytic properties will be thoroughly explored.
Tutor: Tkachenko Serhii, Ph.D.
In this project, the PhD candidate will study shaped electron beams as revolutionary probes, which will make electron microscopes more versatile and cheaper, and enable novel applications. Phase plates needed for the preparation of shaped beams will be explored. Tunable light- or microelectronics-based electron phase plates will be designed and optimized concerning selected applications in imaging and spectroscopy.
Low energy ion scattering (LEIS) is an extremely surface sensitive technique that can quantitatively analyse the outermost atomic layer of a material. The only element that cannot be evaluated directly by this technique is hydrogen since it is lighter than the projectiles of noble gas ions used in LEIS. The flat panel displays (FPDs) found in cell phones, displays, electronics, and computers are a crucial part of a modern technology. A higher resolution of the FPDs can be achieved taking the full control on glass surfaces used in this technology. Surface hydroxyls (-OH) are the most important functional groups on a glass surface, they influence the FPDs technology and performance of FPDs. It is difficult to characterise the hydroxyl groups with selective sensitivity to the top atomic layer by standard methods. The novel tag-and-count approach for quantifying hydroxyl (consequently surface silanol) densities is developing in our collaboration with Brigham Young University (USA) and Corning corporation (USA). The first successful results were recently published in Applied Surface Science (please see for more information). The hydroxyls are selectively marked by Zn atoms during atomic layer deposition. The marked (tagged) groups are then analysed (quantified) by HS-LEIS harvesting the extreme surface sensitivity of the technique. The proposed topic for PhD study will continue this promising research and collaboration with both institutions in USA. The applicant (student) will be involved in both, the tagging technology done in USA and LEIS analysis in Ceitec BUT. For tag-and-count approach see: https://doi.org/10.1016/j.apsusc.2022.154551 For HS-LEIS see for example: https://pubs.acs.org/doi/10.1021/acs.langmuir.5b01935
Automated real-time analysis of the structure and morphology of high-performance polymeric materials and composites is of utmost importance in order to enable their fast development and production. The objective of the PhD project is to explore the possibilities of X-ray computed tomography (CT) scanning for the quantification and digitization of composite material structures. You will test the limits of standard CT imaging setup for the future usage of in-line systems and use simulations to explore alternative and sparse data acquisition to speed up the imaging process. These simulations will then be used to create a detailed model to establish the experimental parameters and the CT reconstruction procedure.
The use of quantum materials for the preparation of supercapacitors. The candidate will gain experience with quantum materials, various technologies for the preparation of quantum nanomaterials, their characterization, and the preparation of supercapacitors with high efficiency. Supervisor is a Highly Cited Researcher. More at www.pumera.org, more info about the group at www.energy.ceitec.cz. Part of the PhD is training on high tech devices, see www.nano.ceitec.cz
The topic is focused on development of numerical methods for rigorous simulation of electromagnetic wave propagation in arbitrary inhomogeneous media. Namely, we assume investigation of the techniques based on the expansion into plane waves and/or eigenmodes in combination with perturbation techniques. Developed techniques will applied to modeling of light scattering by selected biological samples. Requirements: - knowledge in fields of electrodynamics and optics corresponding to undergraduate courses - basic ability to write computer code, preferably in Matlab.
Dynamic engineering composite structures with autonomous adaptability to external stimuli represent a major engineering challenge with foundational technological and societal implications. Unifying development of dynamic composite building blocks, composite structure design with its additive fabrication technology is foundational for the novel composite platform addressing many challenges current society faces. Scalable synthesis of the palette of building blocks with structurally encoded hierarchical assembly motifs and mechanical and photonic connectivity provides the core knowledge needed for the composites for extreme applications. We prepare palette of structurally and functionally programmed building blocks, develop algorithms for their assembly into load bearing and functional sub-structures with photonic signaling, control and power infrastructure in-situ in the course of fabricating engineering composites. Programing composite performance at the level of its building blocks will instigate a paradigm shift in design and fabrication of satelites and spacecrafts, shock resistant surface and air transport vehicles, lightweight armour, earthquake resistant civil engineering structures and tunable acoustic damping structures. The primary goal is a facile preparation of a palette of structural and functional building blocks with encoded mechanical and photonic connectivity and processes for their use in a multi-step fabrication of dynamic engineering composite structures.
Single-atom catalysis promises to make emerging green technologies economically viable, but the atomic-scale details needed for further development are difficult to achieve on working catalysts. In this Ph.D. study, an atomically-resolved surface science approach will be applied to unravel the fine details of single-atom reactivity. The main focus will be on the adsorption properties of single atoms stabilized by organic ligands within 2D metal-organic frameworks (MOFs). These systems will be synthesized on graphene substrates, which allows for disentangling the effects of the coordination geometry and substrate-MOF charge transfer. The systems will be studied experimentally by atomically-resolved imaging (scanning tunneling microscopy), diffraction (low energy electron diffraction/microscopy), and spectroscopic techniques (X-ray/UV photoemission). The experimental results will be interpreted in close collaboration with computational physicists. Finally, the reactivity studies will be carried out in collaboration with our partners at TU Wien, primarily by temperature-programmed desorption and infrared absorption-reflection spectroscopy. For more information, please, contact Jan Čechal or Zdeněk Jakub.
Control over thin molecular films composed of single-molecule magnets or quantum bits is crucial in the development of novel electronic and magnetic devices. Their behaviour on surfaces is yet largely unexplored area. This PhD project will use the already existing high-vacuum chamber for thermal sublimation of thin films of coordination transition metal and lanthanide complexes. The student will work on the whole route from a bulk as-synthesised powder to a nanostructured thin film. The final goal is to be able to predict and evaluate the magnetic properties of such films by newly built high-frequency electron spin resonance spectrometer (HF-ESR). Additional surface-sensitive spectroscopic and microscopic methods such as X-ray photoelectron spectroscopy (XPS), atomic force microscopy (AFM), and scanning electron microscopy (SEM) will be used to study prepared thin films. The student will communicate and perform tasks in international collaboration with research groups in the USA and Italy.
While additive manufacturing of polymers, has become increasingly popular for design studies, rapid prototyping and the production of noncritical spare parts, its application in structurally loaded components is still scarce. One of the reasons for this might be skepticism of engineers due to the lack of knowledge regarding the expected lifetime and reliability as well as knowledge to failure mechanisms. Therefore presented work will be focused on fatigue damage of additively manufactured polymer materials, experimental testing of such materials as well as on numerical modeling of fatigue damage and fatigue crack propagation. This work will be solved in close cooperation with PCCL- Polymer Competence Center in Leoben.
Tutor: Hutař Pavel, prof. Ing., Ph.D.
Lowdensity mechanical metamaterials v structurally tunable acoustic damping and shape memory represent a major engineering challenge with foundational technological and societal implications. Advancements in their theoretical description has not, so far, been accompanied by experimental validations of the predicted effects. Unifying development of geometry and materials of their building blocks, algorithmization of the design of their function specific spatial arrangement and an industrial scale fabrication technology are critical for their practical deployment. Palette of universal building blocks with hybrid structural geometry, shape memory and functionalities enabling their spatially precise connectivity represent the core knowledge critical for effective fabrication of mechanical metamaterials with a broad range of applications. Programing elastic moduli, Poisson´s ratio, 3D tunable dumping of vibration spektra and coefficient of thermal expansion at the level of geometry and materias of the building blocks will instigate a paradigm shift in design of enhanced crashworthiness cars, aircrafts and space ships, explosion and ballistic resistant civil and military structures, vibration damping and tunable band gap acoustic structures, senzors, medical stents and bionic prostheses. The primary goal is a facile preparation of a palette of polymer nanocomposites with shape memory, algorithmization of the design of universal geometrically hybrid building blocks and assembly of digitally orchestrated sequence of deposition processes for their assembly into auxetics with 3D tunable vibration dumping.
Our thorough understanding of magnetic properties is intricately inter-linked with a detailed information about the structure of studied materials. The decreasing particle size and/or temperature resulted in the past few years to the observation of new magnetic states, for example, the superparamagnetism. Importantly, the magnetic states sensitively depend on the atomic structure, crystal boundaries and/or magnetic domains which all significantly change with the temperature. The proposed PhD study will therefore focus on these structure-property relations at low temperatures. The following aspects will be covered: - Preparation of samples by various methods - Structural study of materials by XRD, SEM, TEM, AFM etc. - Magnetic measurements by VSM, PPMS and SQUID
The doctoral thesis will deal with research in the field of catalytic reactions using analytical methods capable of monitoring reactions in real-time. The reactions will be studied by various analytical methods such as UHV-SEM, E-SEM, MS, SIMS etc. aiming to better understand the mechanism of catalytic reactions on different types of surfaces (crystals, nanoparticles) and in a wide range of reaction pressures. In the first phase, the oxidation of carbon monoxide and subsequently other oxidation or reduction reactions important in technical practice will be studied. The work will also include the development of new methods and devices enabling real-time observation under various experimental conditions.
Demineralization of hard tissues (teeth and bones) is a process in which mineral ions (mainly calcium and phosphate) are released from the hydroxyapatite matrix of the tissue. This can occur naturally due to a disease (tooth decay and osteoporosis) and trauma, or artificially through methods such as acid solutions. Demineralization is also associated with accumulated heavy metals in hard tissues. This thesis will be focused on the analysis of demineralized teeth and bones by Laser-Induced Breakdown Spectroscopy. A study of tissues with different demineralization sources, such as heavy metals, caries, or artificial solutions, and a methodology for the early detection of osteoporosis will be the main aims of this thesis.
Holographic incoherent-light-source quantitative phase imaging (HiQPI) is a unique imaging technique developed by our group. It allows obtaining high-quality quantitative phase images of samples, such as living cells, even when they are immersed in a scattering environment. A big challenge for quantitative phase imaging is to achieve super-resolution, as the usual approaches in microscopy are not applicable. Recent calculations, simulations and experiments have shown that in HiQPI it is possible to achieve sub-diffraction resolution (super-resolution) due to partially coherent illumination, which is unique in holographic microscopy. The area of application of quantum Fisher information, allowing to break the classical resolution limit in the case of special types of objects, also remains unexplored. The student will explore various techniques to achieve super-resolution and their utility in HiQPI. Part of the solution to the topic will be a theoretical analysis of each method, a proposal for its implementation in HiQPI and, last but not least, experimental verification on a Q-Phase microscope. The most successful super-resolution technique will then be applied to an experiment with living cells.
Tutor: Chmelík Radim, prof. RNDr., Ph.D.
The electronic configuration of transition metals, characterized by an incomplete subshell and a readiness to donate cations, allows the production of a number of coordination complexes or intermetallics which are represented by a wide range of oxidation states, unique chemical and physical properties having a great potential in new clean and cost-effective renewable energy applications. The doctoral topic will focus on development of green chemistry, mechanochemistry and/or powder metallurgy protocols for synthesis or formation of selected Ti, Fe and Mn transition metal-based complexes, its interaction with various environments, advanced materials properties characterization as well as compaction and sintering into the form of a precursors or targets utilized for thin film deposition technologies. Along the studies, the candidate will have the opportunity to work on development of chemical syntheses routes, and learn a variety of materials characterization and manufacturing technologies. Only, highly motivated and collaborative candidates with outstanding track record and with the ambition in chemistry, materials science and mechanical engineering are welcome to submit an application.
Tutor: Čelko Ladislav, doc. Ing., Ph.D.
Currently there is a big expansion in the development of nanomaterials that find their use in industry. As they become mass spread the risk of leaking into the environment increases and therefore it is necessary to monitor their influence on various ecosystems. Laser-Induced Breakdown Spectroscopy (LIBS) is an optical emission method suitable for elemental mapping of large sample surfaces. The information about biodistribution and bioaccumulation of material in the organism is crucial for correct evaluation of its toxic effect. The LIBS method can detect contaminants in plants with sufficient resolution. The goal of this work is to determine bioaccumulation and translocation of selected nanomaterials in plants.
Tin was historically often used and is still employed nowadays, e.g., in soldering. Interestingly, some aspects of the beta-Sn to alpha-Sn phase transformation (known as tin pest), that turns bulk Sn into a powder, are still not fully understood. Published transformation-related data are, unfortunately, contradictory regarding (1) the mechanism of transformation, (2) the influence of solutes as well as (3) details of the so-called inoculation (insertion of the alpha-Sn into supercooled beta-Sn). The aim of the proposed PhD study is to perform theoretical calculations that will shed a new light on the above mentioned three problems. The calculations will be interlinked with experiments within the Czech Science Foundation project No. 22-05801S in period 2022-2024.
Holographic Incoherent-Light-Source Quantitative Phase Imaging (HiQPI) is a unique imaging technique developed at BUT. Experiments and simulations have shown that it is possible to reconstruct the three-dimensional refractive-index distribution of the observed object from a set of images obtained by this technique. It utilizes the unique coherence gate effect, which occurs when using a low-coherence source. The aim of the work will be to explore different approaches to 3D sample imaging and compare their parameters. The work will include a theoretical analysis of each method, its implementation and experimental verification with a Q-Phase microscope. The most suitable 3D imaging technique will then be employed in a living cell experiment.
Dynamic Nuclear Polarization (DNP) is a phenomenon, that can enhance greatly the NMR sensitivity (several hundred times at least). There are several mechanisms of DNP, though all of them result from the transferring of electron spin polarization (from special polarizing agents) to nucleus. This process is strongly dependent on the electron spin relaxation of the polarizing agent. However, due to the instrument limitations, the spin dynamics of polarizing agents is studied very poorly at frequencies above 100 GHz, especially at frequencies of 263, 329 and 394 GHz, which correspond to NMR proton frequencies of 400, 500 and 600 MHz, respectively. Usually, the spin relaxation properties are studied using the pulsed method. Unfortunately, the nowadays level of microwave sources at THz frequencies, mostly in terms of output power, does not allow the implementation of the pulsed technique in the wide frequency range. For this reason, the Rapid Scan Electron Spin Resonance (RS-EPR) spectroscopy is the only possible technique for the investigation of spin dynamics at THz frequencies. In this project, PhD student will (i) develop and implement a technique of fast frequency sweeps into the high field/high frequency EPR spectrometer (ii) investigate the spin relaxation processes in different DNP polarizing agents in the wide frequency and temperature ranges.
TiO2 is a fascinating material finding applications in optical, electronic, optoelectronic, and sensing devices. TiO2 properties can be modified or fine-tuned by adding another element, thereby creating ternary oxides. It provides new materials for continuous device down-scaling in semiconductor fabrication technology. The Ph.D. topic is focused on atomic layer deposition of Ti-based ternary oxides from the Ti-Si-O and Ti-Sr-O systems. The research should answer the question about the composition-dependent optical and electrical properties and the structure of the deposited films, whether it is well mixed or phase separated.
Tutor: Zajíčková Lenka, doc. Mgr., Ph.D.
Topological insulators (TIs), which demonstrate conductor properties at surfaces and behave as insulator in the bulk, present unique quantum state properties. Therefore, we have witnessed enormous research interest on these materials. It is anticipated that TI materials have a great potential to serve as a platform for spintronics due to their spin-locked electronic states, which could open new avenues for spintronic, quantum computing and magnetoelectric device applications. Moreover, interfacing TIs with superconducting layers is predicted to create mysterious physical phenomena, ranging from induced magnetic monopoles to Majorana fermions. The present PhD study aims at i) synthesizing theoretically studied topological insulators and ii) investigating topological superconductors, formed by hybridizing TIs and superconductor materials. TI and superconductor thin films will be fabricated via employing physical vapor deposition processes such as magnetron sputtering, pulsed laser deposition and molecular beam epitaxy. The obtained films will be characterized by X-ray diffraction method, X-ray Photo-electron Spectroscopy (XPS), Scanning Electron Microscopy (SEM), and HR (S)TEM and so on. Furthermore, the magnetic properties of the thin films will be examined by Vibrating Sample Magnetometer (VSM). In addition, magneto-transport measurements of these films will be carried out as well.
Plasma polymers deposited in cyclopropylamine/argon radio frequency discharge at low pressure proved to be an excellent platform for immobilizing biomolecules and improving cell adhesion and proliferation [E. Makhneva et al. Sens. Actuator B-Chem. 276 (2018) 447,A. Manakhov et al. Materials & Design 132 (2017) 257, A. Manakhov et al. Plasma Process. Polym. 14 (2017) e1600123]. Similarly, plasma polymers containing carboxyl or anhydride groups are perfectly suitable for biomedical applications, as, e.g., the immobilization of drugs and platelet-rich blood plasma were recently reported [E. Permyakova et al. Materials & Design 153 (2018) 60, A. Soloviev et al. Polymers 9(12) (2017) 736]. Plasma polymer thin films are significantly influenced by external parameters such as gas feed composition, pressure, and power to the discharge. Unfortunately, a detailed understanding of plasma polymerization is difficult because it is a complex chemical vapor deposition process that involves many neutral reactants created in the plasma. Moreover, at low pressure, it is affected by positive or negative ions. This thesis aims to understand the plasma-chemical gas phase and surface processes by using plasma diagnostics methods (optical emission spectroscopy, mass and ion spectroscopies, retarding field energy analysis, and Octiv VI Probe measurements). The information gained will be correlated with the characterization of the thin films.
Optimizing the structural design of laser gain media is essential to meet the challenging equirements for laser power, beam quality, efficiency, size, and weight. Due to recent progress in ceramic processing, polycrystalline ceramics opened a pathway to new gain media architecture, which was previously impossible with single crystals. This Ph.D. topic will be aimed at developing ceramic composite structures of optical quality based on yttrium-aluminium garnet doped with rare earth elements. Advanced shaping and sintering technologies based on colloidal shaping, including 3D ceramic printing and high-pressure sintering, will be used to prepare laser ceramics. Ceramics will be evaluated in terms of effectiveness and usability in intended laser applications.
The thesis will focus on finding efficient routes to control magnetic configurations without applied magnetic fields using femtosecond laser stimuli. The physical phenomena involved are linked to ultrafast spin dynamics and the associated energy and angular momentum transfer between the spins, electrons, and lattice. The proposed experimental approach will exploit magnetic heterostructures to generate collective magnetic excitations. The project assumes previous experience with optical set-ups.
The method of laser-induced breakdown spectroscopy, which belongs to the group of atomic emission spectroscopy techniques, has been described as one of the most expanding spectroscopic techniques in recent years, especially in the field of biological and medical research. It is a quasi-destructive analytical method with extensive elemental analysis capabilities that can detect macrobiogenic and microbiogenic elements that compose a given animal tissue. The scope of the dissertation is the complete optimization of the soft tissue measurement parameters of the LIBS technique, together with the processing and interpretation of the obtained data. Furthermore, the implementation of an ideal methodology for soft tissue analysis on model samples. Rodent organs, e.g., polycystic mouse kidneys at different developmental stages, will be the focus of the research. Results from LIBS analyses will be complemented by complementary analytical techniques such as ICP-OES, LA-ICP-MS, or standard optical microscopy (histology).
The study will be aimed at design, fabrication, and characterization of resonant plasmonic nano- and micro-structures (“diabolo” antennas, split ring resonators, etc.) providing a significant local enhancement of magnetic components of electromagnetic fields. The structures with resonant properties particularly in the IR and THz will be studied, with respect to their potential applications in relevant spectroscopic methods.
The doctoral thesis will focus on research and development of new analytical approaches in the field of secondary ion mass spectrometry (SIMS) and electron microscopy for the study of nanostructures and their ability to moderate catalytic reactions (CO oxidation, CO2 hydrogenation etc.). The work will focus on the development of new experimental procedures capable of monitoring the composition of the surface and nanostructures during reactions in real-time.
X-ray micro computed tomography is becoming one of the commonly used imaging methods in the fields of developmental biology and other biological disciplines. In the native sample only the mineralised bones are visible in the microCT scan, the visualization of the soft tissues requires the staining of the sample in the solutions of elements with high proton number. When the scans of the same sample in native and stained condition is combined the time-consuming process of segmenting the mineralised bones from the stained dataset can be skipped, this new approach enables much faster method of analysing the complex biological samples. In the scope of this work the optimising of the staining method of soft tissues and co-registration of both stained and native scans of same sample will be performed.
2D materials for batteries. Candidate will be trained in 2D materials fabrication and applications. MXenes, and black phosphorus materials will be in the focus. Candidate will learn how to use different technologies of 2D materials to achieve desired battery design. He/she will learn how to prepare high performance batteries.
2D materials of functional devices for supercapacitors. Candidate will be trained in 2D materials. Candidate will learn how to use different technologies of 2D materials to achieve desired supercapacitor design. He/she will learn how to prepare high performance supercapacitors.
Supercapacitors (SCs) represent one of the most promising energy storage technologies because of their remarkable features, such as ultrahigh power density and ultralong cycling life. This PhD study aims at an exploration of 2D hybrids based on MXenes and black phosphorous (BP), as high-performance electrode materials for SCs. It will concentrate on (i) multi-scale characterization of 2D hybrids up to atomic resolution to provide fundamental knowledge underlying the interaction between the components of 2D hybrids, and on (ii) an in situ study of chemical stability and growth mechanisms of these materials. In the study, state-of-the-art characterisation methods available at CEITEC Nano core facility such as Low Energy Electron Microscopy (LEEM), UHV STM/AFM, X-ray Photo-electron Spectroscopy (XPS), Low Energy Ion Scattering (LEIS), Scanning Auger Microscopy (SAM), FT-IR Spectroscopy, and HR (S)TEM will be used. The collaboration with the Dresden University of Technology planned to synthesize the 2D materials will be held.
This thesis will focus on the fabrication of new 2D materials for water treatment and purification.
The dissertation thesis will deal with the development of 3D epitaxial printing using eutectic liquid droplets, which are moved by electron beam (electron tweezers) in the UHV-SEM microscope, developed in cooperation with TESCAN. During the movement, the gold-containing droplet is saturated with germanium (silicon) atoms, resulting in epitaxial deposition of the semiconductor at the droplet location. The movement of the droplet and thus also the "print" location of the semiconductor can be controlled programmatically. Part of the work will be optimization of this process including its real-time monitoring using UHV-SEM microscope.
3D printing of batteries. Candidate will be trained in 3D printing. Candidate will learn how to use different technologies of 3D printing to achieve desired battery design. He/she will learn how to prepare high performance batteries.
3D printing for devices for hydrogen evolution. Candidate will be trained in 3D printing. Candidate will learn how to use different technologies of 3D printing to achieve desired water electrolyzer design. He/she will learn how to prepare high performance electrolyzers for hydrogen evolution.
3D printing of functional devices for supercapacitors. Candidate will be trained in 3D printing. Candidate will learn how to use different technologies of 3D printing to achieve desired supercapacitor design. He/she will learn how to prepare high performance supercapacitors.
The topic deals with 4D printing, i.e. 3D printing where 4 dimensions are time and applications for biomedicine. Supervisor, Prof. Pumera, is highly cited researcher, see www.pumera.org, more info about the group on www.energy.ceitec.cz PhD candidate will be trained to use high end equipment at nano.ceitec.cz
Study plan wasn't generated yet for this year.