Frequency-dependent ionic conductivity in (Ag 2S) x(GeS 2) 1 − x glasses

Abstract

Following the theoretical model of the polarization conductivity of ionically conducting glasses, based on the notion of ionic “free-volume” fluctuations, a new procedure is envisaged to explain the experimental results. This procedure allows us to ascribe a precise physical significance to experimentally determined parameters. On the basis of (Ag 2S) x (GeS 2) 1 − x glasses, we have demonstrated, without ambiguity, that the polarization conductivity dependence on temperature and frequency could be expressed as A( T) ω s( ω, T) . It is found experimentally that s is a function of temperature T and frequency ω. This result is interpreted theoretically by using the notions of thermal agitation energy and the “bound-charge” concept usually used to describe the polarization phenomena.