Flexomagnetic effect in Mn-based antiperovskites

TL;DR

This paper demonstrates the flexomagnetic effect in Mn-based antiperovskites, showing how strain gradients induce magnetization at the atomic level, with potential implications for strain-engineered magnetic devices.

Contribution

It provides a detailed atomic-level mechanism of flexomagnetism in Mn_{3}GaN and quantifies the flexomagnetic coefficient, highlighting the effect's linearity and dominance at moderate strain gradients.

Findings

Flexomagnetic effect is linear and strain-gradient dependent.

Induced magnetization is solely due to flexomagnetic contribution at moderate strain gradients.

Flexomagnetic coefficient estimated as 1.95 μ_B*angstrom.

Abstract

We report appearance of the net magnetization in Mn-based antiperovskite compounds as a result of the external strain gradient (flexomagnetic effect). In particular, we describe the mechanism of the magnetization induction in the Mn_{3}GaN at the atomic level in terms of the behavior of the local magnetic moments (LMM) of the Mn atoms. We show that the flexomagnetic effect is linear and results from the non-uniformity of the strain, i.e. it is absent not only in the ground state but also when the applied external strain is uniform. We estimate the flexomagnetic coefficient to be 1.95 mu_{B}*angstrom. We show that at the moderate values of the strain gradient (~ 0.1%) the flexomagnetic contribution is the only non-vanishing input to the induced magnetization.