Large nonvolatile control of magnetic anisotropy in CoPt by a ferroelectric ZnO-based tunneling barrier

TL;DR

This paper demonstrates a significant nonvolatile electric control of magnetic anisotropy in a CoPt/ZnO interface, combining first-principles calculations and experimental measurements, with potential applications in memory devices.

Contribution

It reveals a large, nonvolatile control of magnetic anisotropy via ferroelectric ZnO, driven by orbital hybridization and spin-orbit coupling, supported by both theoretical and experimental evidence.

Findings

Large change in magnetic anisotropy with electric polarization switching

Experimental validation through tunneling resistance measurements

Correlation between magnetic anisotropy control and tunneling anisotropic magnetoresistance

Abstract

The electric control of magnetic anisotropy has important applications for nonvolatile memory and information processing. By first-principles calculations, we show a large nonvolatile control of magnetic anisotropy in ferromagnetic/ferroelectric CoPt/ZnO interface. Using the switched electric polarization of ZnO, the density-of-states and magnetic anisotropy at the CoPt surface show a large change. Due to a strong Co/Pt orbitals hybridization and a large spin-orbit coupling, a large control of magnetic anisotropy was found. We experimentally measured the change of effective anisotropy by tunneling resistance measurements in CoPt/Mg-doped ZnO/Co junctions. Additionally, we corroborate the origin of the control of magnetic anisotropy by observations on tunneling anisotropic magnetoresistance.