Eur. Phys. J. D (2022) 76: 40
https://doi.org/10.1140/epjd/s10053-022-00367-w

Regular Article – Optical Phenomena and Photonics

Suppression of photo-darkening effect after exposure of light on Sb doped InSe₄ films

Laser Laboratory, Department of Physics, Guru Jambheshwar University of Science and Technology Hisar, 125001, Hisar, Haryana, India

^a kavita160781056gjuh@gmail.com

Received: 1 December 2021
Accepted: 14 February 2022
Published online: 7 March 2022

Abstract

This present work focuses on the comparative study of InSe₄ and Sb doped InSe₄ films to investigate the effect of exposure time on the optical constants that are extracted from the absorbance and the transmittance data in the spectral range from 200 to 2500 nm. A tungsten lamp was used for exposure to study the influence of the illumination on the optical properties of the synthesized films. The crystallinity of InSe₄ pure film was increased, whereas reverse effect was analyzed in doped film. The crystallite size of illuminated InSe₄ and In_0.9Se₄Sb_0.1 films was determined using Debye–Scherrer's formula. Tauc's plot was used to calculate the band gap of lit and un-illuminated films. The photo-darkening effect was observed in InSe₄ film due to the reduction in the band gap value with exposure time. Photo-darkening was decreased in InSe₄ film when it was doped with antimony (Sb). Wemple–Di-Domenico (WDD) model was used for examining the refractive index of the pure and doped films. Single oscillator energy (E_o) and dispersion energy (E_d) were estimated for synthesized film samples. The static refractive index and lattice dielectric constant for both pristine InSe₄ and antimony-doped InSe₄ films were calculated.