Impedance Characteristics of γ-Irradiated (TlGaSe2)1 –x(TlInS2)x Solid Solutions

Charge transport in (TlGaSe 2 ) 1 – x (TlInS 2 ) x solid solutions in the frequency range of 20–10 6 Hz before and after γ irradiation is studied using impedance-spectroscopy methods. The relaxation character of the permittivity dispersion and the nature of the dielectric loss are established. The frequency dependence of the dissipation factor tanδ in the crystals of the (TlGaSe 2 ) 1 – x (TlInS 2 ) x solid solutions is caused not only by relaxation polarization, but also by reach-through conductivity. The relaxation times are found to be τ = 10 –3 s. It is determined that, in the frequency range of 10 5 –5 × 10 5 Hz, the electrical conductivity obeys the regularity σ ~ f S (0.1 ≤ S ≤ 1.0), which is indicative of the conductivity over localized states. It is shown that a further increase in the frequency leads to an increase in the ionic conductivity and transition of the system to the superionic state.