Optical Properties of Amorphous As-Se Thin Films

Abstract

Photostructural transformations in amorphous films of chalcogenide glasses (ChG) under light irradiation present scientific and practical interests. From scientific point of view, because the composition of ChG determine the kind of structural units and the mean coordination number, in the present work the amorphous films of the chalcogenide systems As100-xSex (x=40÷98) and As40Se60:Sny (y=0÷10.0 at.% Sn) were studied. The experimental investigation of the transmission spectra, photodarkening relaxation and holographic characteristics of the amorphous films under study, including the thickness dependence are presented. The dependences of the refractive index under light irradiation and heat treatment were revealed. It was established that the more sensitive to light irradiation are the amorphous films of As60Se40 and As50Se50, which exhibit big modifications of the refractive index ((Δn/n) = 0.394).