Coexistence of non-trivial van der Waals magnetic orders enable field-free spin-orbit torque switching at room temperature

Bing Zhao; Lakhan Bainsla; Soheil Ershadrad; Lunjie Zeng; Roselle Ngaloy; Peter Svedlindh; Eva Olsson; Biplab Sanyal; Saroj P. Dash

arXiv · 2308.13408

Coexistence of non-trivial van der Waals magnetic orders enable field-free spin-orbit torque switching at room temperature

Bing Zhao·Lakhan Bainsla·Soheil Ershadrad·Lunjie Zeng·Roselle Ngaloy·Peter Svedlindh·Eva Olsson·Biplab Sanyal·Saroj P. Dash

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Abstract

The discovery of van der Waals (vdW) magnetic materials exhibiting non-trivial and tunable magnetic interactions can give rise to exotic magnetic states, which are not readily attainable with conventional materials. Such vdW magnets can provide a unique platform for studying new magnetic phenomena and realizing magnetization dynamics for energy-efficient and non-volatile spintronic memory and computing technologies. Here, we discover the coexistence of ferromagnetic and antiferromagnetic orders in vdW magnet (Co0.5Fe0.5)5-xGeTe2 (CFGT) CFGT above room temperature, inducing an intrinsic exchange bias and canted perpendicular magnetism. Such non-trivial intrinsic magnetic order enables us to realize energy-efficient, magnetic field-free, and deterministic spin-orbit torque (SOT) switching of CFGT in heterostructure with Pt. The devices show a very large spin Hall conductivity, a low critical current density, and yield a large SOT effective field. These experiments, together with density functional theory and Monte Carlo simulations establish coexisting non-trivial magnetic orders in CFGT that enable field-free SOT magnetization dynamics in spintronic devices.

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Bing Zhao, Lakhan Bainsla, Soheil Ershadrad, Lunjie Zeng, Roselle Ngaloy, Peter Svedlindh, Eva Olsson, Biplab Sanyal, Saroj P. Dash. 2024-10-10. Coexistence of non-trivial van der Waals magnetic orders enable field-free spin-orbit torque switching at room temperature. https://arxiv.org/abs/2308.13408

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