Ac conductivity and its scaling behavior in borate and bismuthate glasses

In the present work, ac conductivity measurement and its compositional dependence scaling analysis are studied on lithium and sodium based borate and bismuthate glasses in the frequency range from 20 Hz to 1 MHz at different temperatures. The measured conductivity data of these glasses are analyzed using Cole-Cole type impedance response function, Jonscher's universal power law and Dyre's random free energy barrier model. To get a consistent stand point on ion dynamics, different microscopic models and theories proposed for the ion conduction mechanism in disordered ionic solids are discussed and compared. Universality features of ac conductivity and its scaling behavior are discussed. The compositional dependence scaling behavior in borate and bismuthate glasses are studied using Jonscher's power law hopping frequency omega(p) and minimum jump frequency gamma(min) in Dyre's random free energy barrier model. The scaling results are compared and reported.