Selectively controlled ferromagnets by electric fields in van der Waals ferromagnetic heterojunctions

TL;DR

This study demonstrates electrically controlled charge transfer in van der Waals heterostructures, enabling selective tuning of ferromagnetic properties and magnetic anisotropy, which could advance spintronic device development.

Contribution

It introduces a method for electrically manipulating charge transfer in magnetic heterostructures to selectively control ferromagnetic properties.

Findings

Charge transfer can be electrically tuned in heterostructures.

Magnetic anisotropy energy of Fe3GeTe2 is significantly modified.

Coercivity of Fe3GeTe2 is dramatically suppressed.

Abstract

Charge transfer plays a key role at the interfaces of heterostructures, which can affect electronic structures and ultimately the physical properties of the materials. However, charge transfer is difficult to manipulate externally once the interface formed. Here, we report electrically tunable charge transfer in Fe3GeTe2/Cr2Ge2Te6/Fe3GeTe2 all-magnetic van der Waals heterostructures, which can be exploited to selectively modify the magnetic properties of the top or bottom Fe3GeTe2 electrodes. The directional charge transfer from metallic Fe3GeTe2 to semiconducting Cr2Ge2Te6 remarkably modifies magnetic anisotropy energy of Fe3GeTe2, leading to the dramatically suppressed coercivity. The electrically selective control of ferromagnets demonstrated in this study could stimulate the development of spintronic devices based on van der Waals magnets.