Reversible control of Co magnetism by voltage induced oxidation

TL;DR

This paper demonstrates reversible voltage-controlled manipulation of Co film magnetism through oxidation state changes, enabling large, nonvolatile magnetic anisotropy modifications with low energy consumption for spintronic applications.

Contribution

It introduces a method to reversibly control Co magnetism via voltage-induced oxidation, achieving significant magnetic anisotropy changes in a nonvolatile manner.

Findings

Magnetic properties of Co films can be reversibly tuned by voltage.

Large magnetic anisotropy energy change of 0.73 erg/cm2 achieved.

Voltage control enables ultra-low energy magnetization manipulation.

Abstract

We demonstrate that magnetic properties of ultra-thin Co films adjacent to Gd2O3 gate oxides can be directly manipulated by voltage. The Co films can be reversibly changed from an optimally-oxidized state with a strong perpendicular magnetic anisotropy to a metallic state with an in-plane magnetic anisotropy, or to an oxidized state with nearly zero magnetization, depending on the polarity and time duration of the applied electric fields. Consequently, an unprecedentedly large change of magnetic anisotropy energy up to 0.73 erg/cm2 has been realized in a nonvolatile manner using gate voltages of only a few volts. These results open a new route to achieve ultra-low energy magnetization manipulation in spintronic devices.