Dielectric relaxation in oxide glasses

Abstract

Dielectric relaxation spectra of lithia-containing silicate glasses and V₂O₅-P₂O₅ glasses respectively have been analysed using a heterophase conductor model developed recently. The model considers the glass as comprising diagonal layers of phases having widely different electrical conductivities. The conducting phase is assumed to have a local conductivity varying sinusoidally with the spatial co-ordinate. Excellent agreement between the experimental data and the theoretical values have been obtained over a broad frequency spectrum. The Kohlrausch-Williams-Watts (KWW) exponent has also been estimated for all the glasses. The exponent appears to be related to the conductivity fluctuation-a higher value of the latter leading a lower value of and vice versa.