Akademik Məlumat İdarəetmə Sistemi
Solid State Communications, vol.405, 2025 (SCI-Expanded)
In this study, the dependencies of the dielectric permittivity, the tangent of the dielectric loss angle, and the electrical conductivity of the FeGaInSe4 crystal on the frequency of the electric field (5 × 104–106 Hz) were investigated within the temperature range of 190–300 K. It was found that the decrease in the real part of the dielectric permittivity with increasing frequency is associated with the reduced ability of dipoles to reorient. In the frequency range of 5 × 104–106 Hz, FeGaInSe4 exhibits normal dispersion, and the distribution of defect lifetimes follows the relation n(τ) ∼ τ−1.77. The increase in dielectric permittivity with temperature is primarily attributed to the rise in defect concentration. The experimentally observed monotonic decrease in the imaginary part of the dielectric permittivity with increasing frequency indicates the presence of relaxation dispersion in FeGaInSe4. The activation energies for this crystal have been determined. The temperature dependence of dielectric loss is related to both the relaxation mechanism and the contribution of electrical conductivity to the dielectric response. It was established that the frequency dependence of conductivity in the 5 × 104–106 Hz range follows the relation σ ∼ fS (with 0.1 ≤ s ≤ 1.0). According to the Correlated Barrier Hopping (CBH) model, in the temperature range of 190–240 K, electrons in the studied material hop between localized states by overcoming potential barriers. The maximum height of the potential barrier was found to be 0.21 eV. Electrical conductivity in FeGaInSe4 is governed by two mechanisms: band conduction and hopping conduction. The coexistence of these two mechanisms can ensure the stable performance of the material under various temperature conditions. This makes it a promising material for applications such as energy storage devices, memory elements, and semiconductor sensors.