Heat capacity anomaly near magnetic phase transition in GaFeO$_3$

TL;DR

This study reports the first observation of a heat capacity anomaly near the magnetic transition in GaFeO3, confirming its behavior as a 3-D Heisenberg ferromagnet through multiple experimental analyses.

Contribution

First observation of heat capacity anomaly in GaFeO3 near magnetic transition, with analysis confirming 3-D Heisenberg ferromagnet behavior.

Findings

Heat capacity anomaly observed near magnetic transition.

Critical exponent α = -0.2(1) consistent with 3-D Heisenberg ferromagnet.

Amplitude ratio A_+/A_- = 1.2(1) supports the magnetic behavior.

Abstract

A heat capacity anomaly in the vicinity of magnetic transition was observed in single crystal GaFeO3 for the first time. The crystals grown along the expected electric polarization direction were characterized by X-ray diffraction, M\"ossbauer and magnetic measurements. Two separate data analyses of heat capacity showed similar results within the experimental accuracy. Critical exponent, {\alpha}=-0.2(1), and amplitude ratios of positive and negative reduced temperatures near the critical point, A_+/A_-=1.2(1), are consistent with behavior of a 3-D Heisenberg ferromagnet.