Large Perpendicular Magnetocrystalline Anisotropy at Fe/Pb(001) interface

TL;DR

This study demonstrates that ultrathin Fe layers on Pb(001) substrates exhibit exceptionally large perpendicular magnetocrystalline anisotropy energy, which can be enhanced and tuned via multilayer structures and charge injection, promising for spintronics.

Contribution

The paper reveals a novel method to achieve large PMA in Fe/Pb(001) interfaces through first-principles calculations, highlighting the role of magnetic proximity effects and multilayer engineering.

Findings

MAE of 7.6 meV in Fe/Pb(001) with half monolayer Fe

MAE increased to 13.6 meV with multilayer structures

MAE can be tuned by charge injection

Abstract

Search for ultrathin magnetic film with large perpendicular magnetocrystalline anisotropy (PMA) has been inspired for years by the continuous miniaturization of magnetic units in spintronics devices. The common magnetic materials used in research and applications are based on Fe because the pure Fe metal is the best yet simple magnetic material from nature. Through systematic first-principles calculations, we explored the possibility to produce large PMA with ultrathin Fe on non-noble and non-magnetic Pb(001) substrate. Interestingly, huge magnetocrystalline anisotropy energy (MAE) of 7.6 meV was found in Pb/Fe/Pb(001) sandwich structure with only half monolayer Fe. Analysis of electronic structures reveals that the magnetic proximity effect at the interface is responsible for this significant enhancement of MAE. The MAE further increases to 13.6 meV with triply repeated capping Pb and intermediate Fe layers. Furthermore, the MAE can be tuned conveniently by charge injection.