THE ROLE OF EXCITONS IN THE FORMATION OF A PHOTOCURRENT IN A TlGaSe<sub>2</sub> SINGLE CRYSTAL


Dzhafarova S. Z.

International Conference on Modern Trends in Physics, Baku, Azerbaijan, 1 - 03 May 2019, pp.36-38, (Full Text) identifier

  • Publication Type: Conference Paper / Full Text
  • City: Baku
  • Country: Azerbaijan
  • Page Numbers: pp.36-38
  • Azerbaijan State University of Economics (UNEC) Affiliated: Yes

Abstract

The paper presents data on the exciton states in the process of photocurrent formation in TlGaSe2.An inverse correlation (maximum absorption-minimum photocurrent) between the exciton absorption lines and extremes of the photocurrent was established based on a detailed analysis of the photocurrent spectra and TlGaSe2 crystal absorption in a wide energy range (2.0 divided by 2.5 eV) and temperatures (1.8 divided by 300 K).These are interpreted on the basis of non-photoactive absorption near the surface. Studies of the temperature dependence of the photocurrent showed that it is non-monotonic with discontinuous features. The non-monotonic temperature dependence of the photocurrent is explained by the presence of recombination levels (r- and s-centers) in the gap with active interaction with sticking levels. It was also established that the observed abrupt changes in the photocurrent at 105, 117 and 210 K are associated with phase transformations in TlGaSe2.