Interstitial bismuth dimers and single atoms as possible centres of broadband near-IR luminescence in bismuth-doped glasses

TL;DR

This study uses computational methods to explore how interstitial bismuth atoms and dimers contribute to broadband near-IR luminescence in various bismuth-doped glasses, extending existing models.

Contribution

It introduces a computational analysis of interstitial bismuth species' spectra, supporting an extended model of near-IR luminescence in bismuth-doped glasses.

Findings

Identification of spectral features of Bi^0 and Bi^{2-} in glasses

Support for interstitial bismuth centers as luminescence sources

Extension of previous luminescence models

Abstract

Absorption, luminescence and Raman spectra of interstitial bismuth atoms, $\mathrm{Bi}^{0}$, and negatively charged dimers, $\mathrm{Bi}^{2-}$, in alumosilicate, germanosilicate, phosphosilicate and phosphogermanate glasses networks are calculated by time-dependent density functional method. On grounds of this calculation an extension of our previously suggested model of broadband near-IR luminescence in bismuth-doped glasses is put forward.