Photoresponse of Tellurium Rich TexSe(1−x) Nonlinear Optical Semiconductors

Abstract

AbstractThe optical properties of TexSe(1−x) were studied for x = 0.8, 0.9, and 1.0. The results for variable temperature, polarization sensitive, spectral photoconductivity measurements on oriented single crystals, as well as the energy band gaps and their temperature dependencies are presented. In all cases, the band gap was found to increase with increasing temperature. Analytical expressions describing the temperature dependent behavior are reported. Furthermore, for the first time the characteristic two peak spectrum of tellurium was separated into its two components for incident radiation polarized parallel and perpendicular to the c-axis as a function of temperature. However, two distinct peaks were not discernible in the alloys, with or without polarization, although the signal intensity was slightly polarization dependent.