Microscopic theory of temperature-dependent magnetoelectric effect in Cr2O3

TL;DR

This paper presents a first-principles calculation of the temperature-dependent magnetoelectric response in Cr2O3, revealing the dominant coupling form, its strength, and the role of exchange interactions and spin fluctuations in its temperature dependence.

Contribution

It provides a comprehensive first-principles analysis of the temperature-dependent magnetoelectric effect in Cr2O3, combining symmetry, ab initio, and Monte Carlo methods.

Findings

Quantitative agreement with experimental data.

Temperature dependence driven by exchange interactions and spin fluctuations.

Identification of the dominant magnetoelectric coupling form.

Abstract

We calculate the temperature-dependent magnetoelectric response of Cr2O3 from first principles. The form of the dominant magnetoelectric coupling is determined using symmetry arguments, its strength is found using ab initio methods, and the temperature dependence of the response is obtained from Monte Carlo simulations. The quantitative agreement of our results with experiment shows that the strong temperature dependence of the magnetoelectric effect in Cr2O3 results from non-relativistic exchange interactions and spin fluctuations.