Anomalous In-plane Magnetic Anisotropy in Strain-mediated Converse Magnetoelectric Coupling

TL;DR

This study uses density functional theory to investigate the unexpected in-plane magnetic anisotropy behavior in strained ferromagnetic materials, revealing complex energy interactions that influence magnetoelectric coupling.

Contribution

It provides the first computational analysis of anomalous in-plane magnetic anisotropy in strain-deformed ferromagnetic materials, highlighting complex energy interactions.

Findings

Short axis is more energy-favorable at high in-plane strain difference.

Anomalous energy trend explains the failure of spin-lattice dynamics simulations.

Couplings between energy terms and high order coefficients are involved.

Abstract

Magnetic axis rotation (MAR) in ferromagnetic (FM) layers is crucial for strain-mediated converse magnetoelectric coupling. Employing the density functional theory (DFT), we computationally study the magnetic anisotropy of selected deformed FM materials such as body-centered iron. The results show that the short axis is more energy-favorable at high in-plane strain difference than previously predicted phenomenologically. This anomalous trend and the complex energy behaviors at different strain conditions explain why spin-lattice dynamics (SLD) simulation does not produce in-plane MAR and imply couplings between different energy terms together with high order coefficient contributions.