Electrical Properties of FeGa0.4In1.6Se4 at Alternating Current

Abstract

The temperature and frequency dependences of the dielectric constant and electrical conductivity of FeGa_0.4In_1.6Se₄ crystals on alternating current have been studied. In the FeGa_0.4In_1.6Se₄ crystal, normal dispersion occurs in the frequency range 2 × 10²–10⁴ Hz, and the lifetime distribution of defects obeys the law n(τ) ~ τ−^1.75. With increasing temperature, the reason for an increase in the value of the real part of the dielectric constant is an increase in the concentration of defects. The experimentally observed monotonic decrease in the imaginary part of the dielectric constant depending on frequency indicates the presence of relaxation dispersion in the FeGa_0.4In_1.6Se₄ crystal. It has been established that, in the temperature range 294.5–343 K at frequencies 2 × 10²–10⁶ Hz, the law σ ~ f ^S (0.1 ≤ S ≤ 1.0) is satisfied for electrical conductivity. It was shown that the conductivity in those crystals is characterized by a band-hopping mechanism. Activation energies were determined from the \(\log \sigma \sim \frac{{{{{10}}^{3}}}}{T}\) dependencies.