Study of thermally activated a.c. conduction in a-Se80Te20 and a-Se80Te19.5M0.5 (M = C, In, Sb) alloys

The temperature and frequency dependence of ac. conductivity in a-Se80Te20 and a-Se80Te19.5M0.5 (M = Cd, In, Sb) alloys have been investigated. Measurements have been carried out for the frequency range 0.5 kHz-10 kHz in the temperature range from room temperature to glass transition temperature. The a.c. conductivity sigma(ac), is found to be proportional to omega(s) where s < 1. The temperature dependence of both sigma(ac), and the parameter s is reasonably well interpreted by the correlated barrier hopping (CBH) model. (C) 2010 Elsevier Masson SAS. All rights reserved.