AC Conductivity and Dielectric Properties οf Amorphous Te₄₂As₃₆Ge₁₀Si₁₂Glass

Abstract

Te42As36Ge10Si12 chalcogenide composition was prepared by conventional melt-quenching. The ac conductivity and the dielectric properties were carried out in the frequency range 0.5 10 3 -4 10 6 Hz and temperature range 300-423 K. The analysis of the experimental results of the frequency dependence of ac conductivity ac() indicates that ac() is proportional to s where s > 1. The temperature dependence of both ac conductivity and the parameter s is reasonably well interpreted by the correlated barrier hopping model. The maximum barrier height Wm calculated from ac conductivity and the density of localized states were determined. Values of dielectric constant 1 and dielectric loss 2 were found to decrease with frequency and increase with temperature. The analysis of dielectric loss leads to determine the barrier height Wm and agrees with that proposed by the theory of hopping of charge carriers over potential barrier between charged defect states as suggested by Elliott in case of chalcogenide glasses.