Laser-induced modification of optical properties of glassy selenium films synthesized by vacuum thermal evaporation

Abstract

The influence of laser radiation at the wavelength of 632.8 nm on the optical properties of ~ 1 µm thick Se (a-Se) glassy films synthesized by vacuum thermal evaporation on quartz substrates has been studied. It is established that an insignificant decrease in their transmittance coefficients (T) and optical gap energy (Eg) is observed after the laser irradiation of the obtained films with a power density of 80 W⋅cm−2. For the first time, an increase in the reflection coefficient (R) and refractive index (n) of the films was detected in the course of long-term relaxation of their amorphous matrix to a more stable state caused by phase changes in a-Se films. It was established that a significant decrease in transmittance and reflection coefficients, refractive index, and Eg occurs after the laser irradiation of a-Se films with a higher power density (5300 W⋅cm−2).