Nonlinear pressure dependence of T_N in almost multiferroic EuTiO_3

TL;DR

This study investigates how the antiferromagnetic transition temperature T_N of EuTiO_3 varies nonlinearly with pressure, revealing a robust AFM phase and consistent exchange interactions, supported by Bloch power law analysis.

Contribution

It demonstrates the nonlinear pressure dependence of T_N in EuTiO_3 and confirms the robustness of the AFM phase under pressure using experimental data and theoretical modeling.

Findings

T_N increases nonlinearly with pressure

Exchange interactions show similar pressure dependence as T_N

AFM transition remains robust under increasing pressure

Abstract

The antiferromagnetic (AFM) phase transition temperature T_N of EuTiO_3 has been studied as a function of pressure p. The data reveal a nonlinear dependence of T_N on p with T_N increasing with increasing pressure. The exchange interactions exhibit an analogous dependence on p as T_N (if the absolute value of the nearest neighbor interaction is considered) and there is evidence that the AFM transition is robust with increasing pressure. The corresponding Weiss temperature {\Theta}_W remains anomalous since it always exhibits positive values. The data are analyzed within the Bloch power law model and provide excellent agreement with experiment.