Atomic Structures and Electronic States of Divalent Bismuth in Bi-Doped Silica Optical Fiber

Abstract

We report first-principles calculations of cluster SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> (24-atom) with and without divalent bismuth (Bi <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2+</sup> ). Heyd-Scuseria-Ernzerhof functional is introduced. The influences of members of “Si-O-Si” rings are considered to study atomic structures, electronic structures, and optical properties of Bi-doped optical fiber. Our results reveal that Bi-doped in 3-membered rings are main contributions to the characteristic absorption bands (around 500 nm), which will lead a red emission in Bi-doped optical fiber. Our methods will be effective to confirm bismuth-active centers for different valence states of Bi atom.