Radim Slovák’s diploma thesis is a comprehensive work that summarizes more than a year of his concentrated efforts. The first chapter summarizes the current state of the art in the field of integrated photonics, with a special focus on the silicon carbide (SiC) platform. In the second chapter, the author presents his own original results of numerical simulations in which he optimized several SiC photonic components (waveguides, gratings, beam splitters, ring resonators) with respect to their functional parameters. The third chapter sums up months of effort towards the optimization of a complex fabrication workflow, and presents the final recipe together with a list of issues that can arise during fabrication. Finally, Radim was also the main person behind the construction of a custom optical setup for characterization of the fabricated components. The results obtained with this setup are presented in the final chapter, where the fabricated components are characterized and the experimental results are compared with numerical simulations. I would like to highlight the degree of independence and focus that the author showed throughout his work. While he turned out to be a good team player, many of the aspects of this work he had to master on his own. This is an exploratory study of high technical quality and as such I recommend awarding it the grade “Excellent”.

The thesis has fulfilled the 2 mandatory goals. It begins with a solid literature review of the state of the art in SiC nanophotonics and quantum photonics. It then presents methods and results on the design/simulation, fabrication, and characterization of silicon carbide–based grating couplers, MMIs and Y-splitters, and ring resonators. The extracted Q-factors of the ring resonators approached 3E3, indicating that a functional processing flow for SiCOI photonic device fabrication has been established. During the process development, the student identified and improved several fabrication-related issues, including inadequate drift compensation, stitching errors, non-merge errors, and crystal-etch defects. The formal layout of the thesis is very good and there are no typographic or grammatical mistakes in English writing. In brief, the thesis meets the standard requirements for a diploma thesis in the given field. Topics for thesis defence:

1. 1. The SiC waveguide propagation loss and grating coupler coupling efficiency could be extracted from the ring resonator measurement results. Please identify the appropriate method and quantify these two important parameters. 2. For the grating coupler simulation, what is the incident angle and collection angle assumed? Has this been considered in the characterization setup? Why was a lensed fiber instead of a standard fiber used in the characterization setup?