Germanium Environment in Simple and Multi-Component Oxide Glasses

Abstract

Germanium is an important oxide glass component, classically compared to Si as a network-forming element, but with possible coordination changes as in the alkali germanates. In multicomponent oxide glasses EXAFS is a method of choice for studying Ge environment because of its atomic selectivity. Furthermore Ge-containing glasses are receiving increased interest due to the use of germanium to create a refractive index gradient in optical waveguide fibres. This application gives special importance to the knowledge of Ge local structure in multicomponent glasses.