The absence of ferroelectricity and the origin of depolarization currents in YFe0.8Mn0.2O3

Abstract

Polarization properties and dielectric relaxations were investigated in single crystalline Mn-substituted YFeO3. Thermally stimulated depolarization currents (TSDC) were observed at T-m approximate to 110K along all three orthorhombic directions but with different magnitudes. These anisotropic behaviors were also observed in temperature dependent dielectric responses. Electric field sweep polarization measurements down to 10K showed neither hysteresis nor remanent polarization. Based on the result of the temperature-and frequency-dependent dielectric measurements and the relaxation analysis of the TSDC, we suggest that previously reported pyroelectric currents at similar to 110K are not due to a ferroelectric phase transition but due to the formation of frozen defect dipoles which are induced by the localized charge carriers. Published by AIP Publishing.