Study of dielectric relaxation and AC conductivity of InP:S single crystal

Department of Physics, Faculty of Education, Ain Shams University, Roxy 11757 Cairo, Egypt

^a e-mail: hend2061@yahoo.com

Received: 12 March 2012
Revised: 2 May 2012
Accepted: 14 May 2012
Published online: 5 July 2012

Abstract

The dielectric relaxation and AC conductivity of InP:S single crystal were studied in the frequency range from 100 to 5.25 × 10⁵ Hz and in the temperature range from 296 to 455 K. The dependence of the dielectric constant (ε₁) and the dielectric loss (ε₂) on both frequency and temperature was investigated. Since no peak was observed on the dielectric loss, we used a method based on the electric modulus to evaluate the activation energy of the dielectric relaxation. Scaling of the electric modulus spectra showed that the charge transport dynamics is independent of temperature. The AC conductivity (σ_AC) was found to obey the power law: Aω^s. Analysis of the AC conductivity data and the frequency exponent showed that the correlated barrier hopping (CBH) model is the dominant mechanism for the AC conduction. The variation of AC conductivity with temperature at different frequencies showed that σ_AC is a thermally activated process.