AC conductivity of (As2Te3)95Ge5

Abstract The elctrical conductivity of amorphous chalcogenide (As 2 Te 3 ) 95 Ge 5 is investigated at variable frequency, from 1 kHz up to 35 GHz, and a variable temperature, from 77 to 300 K. The low-temperature conductivity is constant with temperature at a fixed frequency. At a fixed temperature, it obeys a ω 0.8 law only at low frequencies. The results are analysed with respect to the polaron problem, but also with a simple model of several dilute localized levels having a wide energy distribution in the forbidden band.