Electrical conductivity and dielectric analysis of La0.75(Ca,Sr)0.25Mn0.85Ga0.15O3 perovskite compound

In the present study the tool of impedance spectroscopy was utilized to characterize dielectric behavior of AMn0.85Ga0.15O3 (A = La0.75Ca0.08Sr0.17) composition synthesized by the solid-state reaction. The complex impedance has been investigated in the temperature range 100–360 K and in the frequency range 40 Hz–2 MHz. The Z′ and Z″ versus frequency plots were found to exhibit a semi-circular arc described by an electrical equivalent circuit. The conductivity spectra have been investigated by the Jonscher universal power law: σ(ω) = σdc + Aωn, where ω is the frequency of the ac field, and n is the exponent. The activation energy obtained both from dc conductivity and modulus spectrum are very similar, and hence the relaxation process may be attributed to the same type of charge carriers.

► The AMn0.85Ga0.15O3 compound synthesized by the solid-state reaction.
► Dielectric relaxation in AMn0.85Ga0.15O3 is found to be of non-Debye type.
► The conductivity has been investigated by the Jonscher universal power law.
► A temperature dependence of the relaxation phenomenon is also clearly observed.