The riddle of orange-red luminescence in Bismuth-doped silica glasses

The riddle of orange-red luminescence in Bismuth-doped silica glasses

WoS Article

For over the past two decades it has been believed that the intense orange-red photoluminescence in Bismuth-doped materials originates from Bi2+ ions. Based on the results from magnetic circular polarization experiments, we demonstrate that this hypothesis fails for Bismuth-doped silica glasses. Our findings contradict the generally accepted statement that the orange-red luminescence arises from P-2(3/2)(1)-> P-2(1/2) transition in a divalent Bismuth ion. The degree of magnetic circular polarization of this luminescence exhibits non-monotonic temperature and field dependencies, as well as sign reversal. This complex behaviour cannot be explained under the assumption of a single Bi2+ ion. The detailed analysis enables us to construct a consistent diagram of energy levels involved in the magneto-optical experiments and propose a new interpretation of the nature of orange-red luminescence in Bismuth-doped silica glass. A centre responsible for this notorious photoluminescence must be an even-electron system with an integer total spin, presumably a dimer of Bismuth ions or a complex consisting of Bi2+ and an oxygen vacancy.

For over the past two decades it has been believed that the intense orange-red photoluminescence in Bismuth-doped materials originates from Bi2+ ions. Based on the results from magnetic circular polarization experiments, we demonstrate that this hypothesis fails for Bismuth-doped silica glasses. Our findings contradict the generally accepted statement that the orange-red luminescence arises from P-2(3/2)(1)-> P-2(1/2) transition in a divalent Bismuth ion. The degree of magnetic circular polarization of this luminescence exhibits non-monotonic temperature and field dependencies, as well as sign reversal. This complex behaviour cannot be explained under the assumption of a single Bi2+ ion. The detailed analysis enables us to construct a consistent diagram of energy levels involved in the magneto-optical experiments and propose a new interpretation of the nature of orange-red luminescence in Bismuth-doped silica glass. A centre responsible for this notorious photoluminescence must be an even-electron system with an integer total spin, presumably a dimer of Bismuth ions or a complex consisting of Bi2+ and an oxygen vacancy.

Fiber materials; Laser materials; Spectroscopy, fluorescence and luminescence.

Fiber materials; Laser materials; Spectroscopy, fluorescence and luminescence.

LAGUTA, O.; RAZDOBREEV, I.

2022

08.04.2021

Nature Portfolio

BERLIN

2045-2322

Scientific Reports

11

1

United Kingdom of Great Britain and Northern Ireland

1

10

10

https://www.nature.com/articles/s41598-021-87290-z

http://hdl.handle.net/11012/203219

s41598-021-87290-z