Dielectric Relaxation in Glassy Se100 - x Sbx

Authors : N CHOUDHARY, A KUMAR

Pages : 119-125

View : 20 | Download : 6

Publication Date : 0000-00-00

Article Type : Research Paper

Abstract :Frequency and temperature dependence of dielectric constant \varepsilon` and dielectric loss \varepsilon`` are studied in glassy Se1-x Sbx insert ignore into journalissuearticles values(x = 0, 0.02, 0.04, 0.06, 0.08 and 0.10); in the frequency range from 1--10 kHz and in the temperature range 290 K to 360 K. The experimental results indicate that no dielectric dispersion exist in glassy Se in the operating range of frequencies. However, when Sb concentration increases in Se1-x Sbx insert ignore into journalissuearticles values(x = 0.02, 0.04, 0.06, 0.08 and 0.10); dielectric dispersion starts in the upper frequency and temperature range. The values of \varepsilon` and \varepsilon``, as functions of temperature and frequency, increase with Sb concentration to x = 0.08; at which point a discontinuity is observed. Above 8%, \varepsilon` and \varepsilon`` decrease with Sb concentration. The discontinuity is explained in terms of the mechanically stabilized structure at a particular average co-ordination number. An analysis of the observed dielectric loss shows that the Guintini`s theory of dielectric dispersion based on two electron hopping over a potential barrier is applicable in the present case.
Keywords : Chalcogenide glasses, Dielectric relaxation