Gigantic Current Control of Coercive Field and Magnetic Memory Based on Nanometer‐Thin Ferromagnetic van der Waals Fe₃GeTe₂

TLDR

Controlling magnetic states with small currents is essential for energy‑efficient spintronics, yet changing the magnetic ground state below a phase‑transition temperature typically requires substantial energy. The study aims to demonstrate a new nonvolatile magnetic memory based on Fe₃GeTe₂ that can be controlled by a tiny current. This is achieved by an in‑plane current that generates a gigantic spin‑orbit torque in Fe₃GeTe₂, enabling the tuning of its magnetic state. The authors show that an in‑plane current can switch nanometer‑thin Fe₃GeTe₂ from a hard to a soft magnetic state, substantially reducing its coercive field and opening new possibilities for van der Waals spintronic devices.

Abstract

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. Here, it is reported that, surprisingly, an in‐plane current can tune the magnetic state of the nanometer‐thin van der Waals ferromagnet Fe 3 GeTe 2 from a hard magnetic state to a soft magnetic state. It is a 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 Fe 3 GeTe 2 . In addition, a working model of a new nonvolatile magnetic memory based on the principle of the discovery in Fe 3 GeTe 2 , controlled by a tiny current, is further demonstrated. The findings open up a new window of exciting opportunities for magnetic van der Waals materials with potentially huge impact on the future development of spintronic and magnetic memory.