Strain controllable magnetocrystalline anisotropy in FeRh/MgO bilayers

TL;DR

This study uses ab-initio calculations to show how epitaxial strain in FeRh/MgO bilayers can control magnetocrystalline anisotropy, enabling magnetic easy axis switching for potential spintronic applications.

Contribution

It reveals the strain-induced switching of magnetic easy axis in FeRh/MgO bilayers through detailed electronic structure analysis.

Findings

Strain significantly alters the magnetocrystalline anisotropy.

Epitaxial strain induces a switch from perpendicular to in-plane magnetic easy axis.

The mechanism involves shifts in spin-orbit coupled d-states at the interface.

Abstract

Ultra-thin film of FeRh on insulator MgO substrate has been investigated usingab-initio electronic structure calculations. From this calculation, we have found the interesting effect of epitaxial strain on the magnetocrystalline anisotropy (MCA). Analysis of the energy and k-resolved distribution of the orbital character of the band structure reveals that MCA largely arises from the spin-orbit coupling (SOC) between dx2-y2 andd xz,yz orbitals of Fe atoms at the FeRh/MgO interface. We demonstrate that the strain has significant effects on the MCA: It not only affects the value of the MCA but also induces a switching of the magnetic easy axis from perpendicular to in-plane direction. The mechanism is the strain-induced shifts of the SOC d-states. Our work demonstrates that strain engineering can open a viable pathway towards tailoring magnetic properties for antiferromagetic spintronic applications.