Influence of the composition of (TlGaS2)1–х(TlInSe2)x solid solutions on their physical properties

Abstract

The single crystals of (TlGaS2)1–х(TlInSe2)х (х = 0…0.5) solid solutions have been grown up. The photoelectric, X-ray dosimetric, dielectric and optical characteristics of the (TlGaS2)1-х(TlInSe2)х solid solutions with various compositions have been determined. The maximum and spectral range of photosensitivity were found to redshift as x increases from 0 to 0.5. Both the photo- and X-ray sensitivity of these solid solutions are higher than those of pure TlGaS2. The nature of dielectric losses and the hopping mechanism of charge transport in the (TlGaS2)1–х(TlInSe2)х solid solutions have been established from the experimental results on high-frequency dielectric measurements. The temperature dependences of exciton peak position for various compositions (x = 0…0.3) have been investigated within 77…180 K temperature interval. It has been ascertained that, with increasing x in (TlGaS2)1–х(TlInSe2)х solid solutions, the width of their forbidden gap decreases.

Keywords

• solid solutions
• photosensitivity
• dielectric losses
• exciton peak
• X-ray dosimetry