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arXiv · 1804.00798

Adjustable current-induced magnetization switching utilizing interlayer exchange coupling

Yu Sheng·Kevin William Edmonds·Xingqiao Ma·Houzhi Zheng·Kaiyou Wang
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Abstract

Electrical current-induced deterministic magnetization switching in a magnetic multilayer structure without external magnetic field is realized by utilizing interlayer exchange coupling. Two ferromagnetic Co layers, with in-plane and out-of-plane anisotropy respectively, are separated by a spacer Ta layer, which plays a dual role of inducing antiferromagnetic interlayer coupling, and contributing to the current-induced effective magnetic field through the spin Hall effect. The current-induced magnetization switching behavior can be tuned by pre-magnetizing the in-plane Co layer. The antiferromagnetic exchange coupling field increases with decreasing thickness of the Ta layer, reaching 630+-5 Oe for a Ta thickness of 1.5nm. The magnitude of the current-induced perpendicular effective magnetic field from spin-orbit torque is 9.2 Oe/(107Acm-2). The large spin Hall angle of Ta, opposite in sign to that of Pt, results in a low critical current density of 9*10^6A/cm^2. This approach is promising for the electrical switching of magnetic memory elements without external magnetic field.

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Yu Sheng, Kevin William Edmonds, Xingqiao Ma, Houzhi Zheng, Kaiyou Wang. 2018-04-03. Adjustable current-induced magnetization switching utilizing interlayer exchange coupling. https://arxiv.org/abs/1804.00798

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