AC conductivity and its scaling behavior in MgO–Li2O–B2O3–Bi2O3 glasses

In the present work, the compositional dependence of density, refractive index and glass transition temperature of xMgO-(25-x)Li2O–50B2O3–25Bi2O3 glasses is studied. Impedance spectroscopy technique is employed on these samples and the data are analyzed using Cole–Cole type impedance response function. The AC conductivity behavior of the present glasses has been investigated in the frequency range from 100 Hz to 1 MHz and as a function of temperature the measured AC data are analyzed using the Jonscher’s universal power law to explain the observed dispersive behavior of the electrical conductivity. The temperature and composition dependence scaling behavior in the AC conductivity are satisfactorily explained by scaling the AC conductivity σ′(ω) by hopping frequency ωp. The frequency response of dielectric constant ε′ and dielectric loss tanδ as a function of temperature were studied. The tanδ peak shifts to higher frequency with increasing temperature, indicating dipolar relaxation character of dielectric loss in the present glasses.

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► Work focuses on the AC conductivity of bismuth glasses.
► Presence of alkali and alkaline earth oxides is of interest.
► Conductivity was explained based on the Universal power law.
► DSC and refractive index studies on these glasses are reported.