Abstract

The current investigation was fulfilled for insight into the dielectric properties of Tl₄S₃layered single crystals. The real part of dielectric constant ε^׳, imaginary part of dielectric constant ε^×´, the dissipation factor tan δ and the alternating current conductivity σ_ac were measured in an applied ac electric field of frequencies extending from 2.5 to 50 kHz. These measurements were carried out in low temperatures ranging from 77 to 300 K. In line with the dependencies of these dielectric parameters on frequency and temperature, the dielectric properties of the crystals under investigation were elucidated and analyzed. Furthermore, the ac conductivity was found to obey the power law σ_ac(ω) = Aω^s with which the values of s were evaluated to be less than unity in the range 0.77 ≥ s ≥ 0.69. On increasing the conditional working temperature, the exponent s was found to be linearly decreased with a temperature coefficient of about 3.69 x 10^-4. However, the resultant data showed that the temperature dependence of ac conductivity follows the Arrhenius relation. Based on this dependence, the impact of temperature on the electrical processes in an applied ac electric field was demonstrated and analyzed. In addition, the activation energy was determined for two temperature phases at all the working frequencies investigated here.

Key words: Dielectric properties of layered single crystals, charge transition in chalcogenide semiconductors, electrical conduction in an a.c electric field.