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arXiv · 2108.12111

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

Kaixuan Zhang·Seungyun Han·Youjin Lee·Matthew J. Coak·Junghyun Kim·Inho Hwang·Suhan Son·Jeacheol Shin·Mijin Lim·Daegeun Jo·Kyoo Kim·Dohun Kim·Hyun-Woo Lee·Je-Geun Park
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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.

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Kaixuan Zhang, Seungyun Han, Youjin Lee, Matthew J. Coak, Junghyun Kim, Inho Hwang, Suhan Son, Jeacheol Shin, Mijin Lim, Daegeun Jo, Kyoo Kim, Dohun Kim, Hyun-Woo Lee, Je-Geun Park. 2021-08-27. Gigantic current control of coercive field and magnetic memory based on nm-thin ferromagnetic van der Waals Fe3GeTe2. https://doi.org/10.1002/adma.202004110

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