Thermally induced currents and instabilities of photoresponse in PbTe(In)-based films

Abstract

The thermally induced currents (TIC) and instabilities of photoresponse in Pb1-x-ySnxGeyTe(IN) films on BaF2 substrates have been investigated at temperatures 4.2 < T < 30 K. The temperature TM corresponding to maximum values of single TIC peaks appears to be extremely low varying from 6 K up to 14 K. The combined effect of lighting and slight heating of the sample from 4.2 K up to approximately 6 K results in photoresponse instabilities depending on the experimental regime. The results are interpreted in terms of thermal excitation of charge carriers from metastable impurity level.