Electric conductivity and dielectric relaxation properties of BiFeO3-YMnO3 solid solution.

This manuscript presents a systematic study of conductivity and dielectric relaxations in the solid solution of (BiFeO3)1-x -(YMnO3)x for compositional range (0.0 ≤ x ≤ 0.2) as function of frequency, temperature, and magnetic field. The samples have been synthesized by combustion method. The thermal activations of dc-conductivity and relaxation time obey Arrhenius behavior for, x = 0.0, 0.025, 0.05 but follow variable range hopping of small polarons above, x ≥ 0.075 with activation energy 0.45 eV. The compositional time-temperature superposition of dielectric modulus data suggests that conduction mechanism changes with composition. The bulk capacitance decreases with increase in magnetic field. [ABSTRACT FROM AUTHOR]