Gigantic current control of coercive field and magnetic memory based on nm-thin ferromagnetic van der Waals Fe3GeTe2

TL;DR

This paper demonstrates that a tiny in-plane current can significantly reduce the coercive field in nm-thin Fe3GeTe2, enabling control of magnetic states and proposing a new nonvolatile magnetic memory device based on giant spin-orbit torque effects.

Contribution

It reveals a novel current-induced control of magnetic states in van der Waals ferromagnet Fe3GeTe2 through gigantic spin-orbit torque, leading to potential spintronic applications.

Findings

In-plane current reduces coercive field in Fe3GeTe2.

Gigantic spin-orbit torque observed in the material.

Proposed nonvolatile magnetic memory device.

Abstract

Controlling magnetic states by a small current is essential for the next-generation of energy-efficient spintronic devices. However, it invariably requires considerable energy to change a magnetic ground state of intrinsically quantum nature governed by fundamental Hamiltonian, once stabilized below a phase transition temperature. We report that surprisingly an in-plane current can tune the magnetic state of nm-thin van der Waals ferromagnet Fe3GeTe2 from a hard magnetic state to a soft magnetic state. It is the direct demonstration of the current-induced substantial reduction of the coercive field. This surprising finding is possible because the in-plane current produces a highly unusual type of gigantic spin-orbit torque for Fe3GeTe2. And we further demonstrate a working model of a new nonvolatile magnetic memory based on the principle of our discovery in Fe3GeTe2, controlled by a tiny current. Our findings open up a new window of exciting opportunities for magnetic van der Waals materials with potentially huge impacts on the future development of spintronic and magnetic memory.