Field Dependence of the Interface Energy in Af/FM Bilayers

TL;DR

This paper proposes a microscopic model to explain the variation in interface energy in AF/FM bilayers, accounting for discrepancies in exchange anisotropy field measurements due to field-dependent interface energy influenced by interface roughness.

Contribution

It introduces a simple microscopic model that incorporates interface roughness and explains the field dependence of interface energy in AF/FM bilayers, addressing measurement discrepancies.

Findings

Interface energy depends on the external magnetic field.

The model accounts for differences in exchange anisotropy field measurements.

Field dependence observed in anisotropic magnetoresistance measurements.

Abstract

In the investigations of antiferromagnetic (AF)/ ferromagnetic (FM) bilayer samples, often distinct experimental techniques yield different values for the measured exchange anisotropy field (HE). Using a simple microscopic model for representing the AF/FM interface, which incorporates the effect of interface roughness, we propose that the observed discrepancy may be accounted for by the dependence of the interface energy between the AF and FM layers with the value of the external applied field (H) as recently observed in anisotropic magnetoresistance measurements, lending support to our proposal.