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arXiv · 2207.05968

Boosting spin-orbit torque efficiency in spin-current generator/magnet/oxide superlattices

Lijun Zhu·Jingwei Li·Lujun Zhu·Xinyue Xie
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Abstract

Efficient manipulation of magnetic materials is essential for spintronics. In spin-current generator/magnet bilayers, the efficiency of spin-orbit torques per magnetic layer thickness scales inversely with the magnetic layer thickness, leading to considerable power increase in applications with large magnetic layer thickness. Here, we develop a 3D spin-orbit material scheme in which the spin torque efficiency can be remarkably boosted up by stacking [spin-current generator/magnet/oxide]n superlattices, with the oxide layers breaking the inversion symmetry. In contrast, the spin torque diminishes in [spin-current generator/magnet]n superlattices lacking inversion symmetry breaking. These results advances the understanding of spin-orbit torques in magnetic multilayers and establishes spin-current generator/magnet/oxide superlattices as advantageous bricks for development of high energy-efficiency, high-endurance, and high-density spintronic memory and computing.

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Lijun Zhu, Jingwei Li, Lujun Zhu, Xinyue Xie. 2022-11-25. Boosting spin-orbit torque efficiency in spin-current generator/magnet/oxide superlattices. https://doi.org/10.1103/physrevapplied.18.064052

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