Behavior of Electrical Conductivity and Dielectric Study of Chalcogenide Ag<inf>0.5</inf>(As<inf>40</inf>S<inf>30</inf>Se<inf>30</inf>)<inf>99.5</inf> Glass

Abstract

© 2019, The Minerals, Metals & Materials Society. Electrical properties of amorphous Ag0.5(As40S30Se30)99.5 alloy have been investigated using complex impedance spectroscopy at different temperatures in the frequency range from 100 Hz to 1 MHz. Direct current (DC) conductivity data follows Arrhenius behavior, while the nature of frequency dependence of alternating current (AC) conductivity follows Jonscher’s power law. Impedance spectra were analyzed by means of an equivalent-circuit model that revealed the presence of a temperature-dependent electrical relaxation phenomenon of the non-Debye type. Different activation energy values of conduction and of the relaxation process were obtained, suggesting different mechanisms of conduction and relaxation. Dielectric properties were analyzed where the real part (ε′) and imaginary part (ε″) of the dielectric constant were found to decrease with frequency and increase with temperature. The temperature coefficient of dielectric constant (TCP) is evaluated. The analysis of dielectric loss leads to determination of the barrier height Wm which is found to be 0.086 eV.