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arXiv · 1412.5832

First-principle study of the near-IR luminescence centers in Bi2O3-GeO2 andBi2O3-SiO2 glasses

V. O. Sokolov·V. G. Plotnichenko·E. M. Dianov
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Abstract

First-principle study of bismuth-related oxygen-deficient centers ($=$Bi$\cdots$Ge$\equiv$, $=$Bi$\cdots$Si$\equiv$, and $=$Bi$\cdots$Bi$=$ oxygen vacancies) in Bi$_2$O$_3$-GeO$_2$, Bi$_2$O$_3$-SiO$_2$, Bi$_2$O$_3$-Al$_2$O$_3$-GeO$_2$, and Bi$_2$O$_3$-Al$_2$O$_3$-SiO$_2$ hosts is performed. A comparison of calculated spectral properties of the centers with the experimental data on luminescence emission and excitation spectra suggests that luminescence in the 1.2-1.3 $μ$m and 1.8-3.0 $μ$m ranges in Bi$_2$O$_3$-GeO$_2$ glasses and crystals is likely caused by $=$Bi$\cdots$Ge$\equiv$ and $=$Bi$\cdots$Bi$=$ centers, respectively, and the luminescence near 1.1 $μ$m in Bi$_2$O$_3$-Al$_2$O$_3$-GeO$_2$ glasses and crystals may be caused by $=$Bi$\cdots$Ge$\equiv$ center with (AlO$_4$)$^-$ center in the second coordination shell of Ge atom.

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V. O. Sokolov, V. G. Plotnichenko, E. M. Dianov. 2014-12-18. First-principle study of the near-IR luminescence centers in Bi2O3-GeO2 andBi2O3-SiO2 glasses. https://doi.org/10.1364/ome.5.000163

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