Kinetics of photoinduced absorption in chalcogenide-glass fibers

Abstract

Experimental and theoretical results are presented for the kinetics of photoinduced absorption in chalcogenide glass fibres. Photoinduced absorption measurements were carried out both at room temperature as well as at liquid nitrogen temperature in a wide range of probing light photon energy hw < Eg. Experimental results are interpreted on the bases of the model with quasicontinuous distribution of localized states in the gap. Both experimental and theoretical results show that subbandgap light can not only reduce the previously induced absorption but can produce an enhancement of photoinduced absorption also. It is shown, that photoinduced absorption data can be used for determining the parameters of localized states distribution. Computer simulation of photoinduced absorption kinetics shows a good correlation with experimental results.