Dielectric relaxation in a transition-metal glass

Abstract

The dielectric relaxation data for a range of vanadium oxide/tellurium oxide glasses recently published by Mansingh et al. (1983) has been re-examined and shown to be consistent with the observation of a DC conductivity and a single process of relaxation over the entire ranges of composition, temperature and frequency which have been reported. The relaxation process however has been found not to be of the loss peak form but an example of the low-frequency dispersion process which has been commonly observed in materials containing quasi-free ions, such as beta -alumina. Detailed examination of the temperature dependences of both the dispersion and conductivity processes supports the original proposal that thermally assisted tunnelling of ions governs both the relaxation rate and the conductivity.