Electrical impedance characterization of (AgCl)0.05(AgPO3)0.95 and (AgBr)0.05(AgPO3)0.95 glassy systems over 5 K to 300 K temperature range

Abstract

The electrical properties of doped silver halide silver metaphosphate glasses; (AgCl)_0.05(AgPO₃)_0.95 and (AgBr)_0.05(AgPO₃)_0.95 are investigated. The amorphous character of the glasses is determined by differential scanning calorimetry. The samples are characterized using complex impedance spectroscopy in order to investigate the frequency and temperature dependence of their conductivities. Insights into the conduction processes are obtained. Four conductivity regimes are identified, the dc conductivity which follows an Arrhenius law, the dispersed conductivity which follows Jonscher power law, the Nearly Constant Loss conductivity which shows a slight temperature dependence, and the low-temperature Nearly Constant Loss with no thermal activation. The foundation and the change of the main conductivity mechanism from the translational to the localized electronic as the temperature is decreased are discussed. The difference of ionic mobility in (AgCl)_0.05(AgPO₃)_0.95 and (AgBr)_0.05(AgPO₃)_0.95 glass matrices is detected only in the difference in translational motion, while the localized motion is the same for the two glasses.