Optically and thermally induced modifications of the optical constants of amorphous(as4s3se3)1-x:snx thin films

Abstract

This paper represent the work that has been done to show optically and thermally induced changes of the optically constants in chalcogenide (As4S3Se3)1-x:Snx (x=010 at.%) thin films. The kinetics of optically and thermally induced changes in chalcogenide films were measured by monitoring the change of optically constants, such as optical band gap Egopt, absorption coefficient α, and refractive index n, using a modified computer-controlled spectrophotometer; for data acquisition, the experimental set-up included a digital built-in PC-card PCI-1713A connected to the registration module. The relaxation of photodarkening in amorphous (As4S3Se3)1-x:Snx thin films, which is described by the stretched exponential function T(t)/T(0) = A0 Aexp[-(t-t0)/τ](1-β), was also investigated. Since the amorphous (As4S3Se3)1-x:Snx thin films exhibit photoinduced effects under the light irradiation with photon energy above the optical band gap (hν≥Eg), they are promising materials for registration of optical and holographic information.