Electronic, dielectric properties and charge transfer in a TlGaS-=SUB=-2-=/SUB=- : Nd-=SUP=-3+-=/SUP=- single crystal at direct and alternating current

Abstract

The band structure, density of states, and electronic properties of a 32-atomic supercell of a semiconductor compound TlGaS2 containing neodymium are calculated. On the grown new single crystals of TlGaS2 : Nd3+ (0.3 mol% Nd2S3), experimental results on the physical properties have been obtained. The temperature (93-538 K) and frequency (5·104-3.5·107 Hz) dependences of the dc and ac conductivity and the frequency dispersion of the dielectric coefficients of TlGaS2 : Nd3+ single crystals have been studied. It was found that in TlGaS2 : Nd3+, in the entire studied frequency range, there are losses due to electrical conductivity, and the charge transfer has a hopping character. The parameters of localized states are estimated, such as the density of localized states near the Fermi level and their spread, the average hopping time and distance, and the concentration of deep traps responsible for the dc and ac conductivity in TlGaS2 : Nd3+. Keywords: DFT calculation, TlGaS2 supercell, neodymium doping, energy structure, density of states, dielectric properties, charge transfer, TlGaS2 : Nd3+ single crystal, direct and alternating current.