Magneto-Dielectric Behavior in $La_{0.53}Ca_{0.47}MnO_{3}$

Abstract

We prospect magneto-dielectricity in $La_{0.53}Ca_{0.47}MnO_{3}$ across its paramagnetic (PMI) to ferromagnetic (FMM) isostructural transition at $T_{C} \sim 253K$, by magnetic ($(M)$), caloric ($(W)$), dielectric ($(\epsilon')$), magneto-resistive (MR), and magneto-capacitance (MC) investigations. Skew-broadened first-order transition character is confirmed via heating/cooling hystereses in $(M)(T)$ and $(W)(T)$, with superheating temperature $T**$ almost next to $T_C$ and supercooling temperature $T*$ exhibiting kinetics. Above $T_C$, linearly-related MC and MR reflect purely magneto-resistance effect. Near $T_C$, the high-frequency MC(5T) much exceeds the magneto-losses, and is uncorrelated with dc MR(5T) in the FM-ordered state. The intrinsic magneto-dielectricity manifest below $T_C$ and above ~kHz is traced to an intra-granular Maxwell-Wagner-type effect at the interface-region of PMI-FMM phase-coexistence.