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arXiv · 2504.08394

Giant Orbital Torque-driven Picosecond Switching in Magnetic Tunnel Junctions

Abstract

Orbital Hall effect was recently discovered as a novel pathway for driving magnetic moment. However, the integration of orbital Hall effect in magnetic memories suffers from low orbital-to-spin conversion efficiency and incompatibility with magnetic tunnel junctions. Here we demonstrate an orbital Hall effect-driven magnetic tunnel junction based on Ru/W bilayer, where the Ru layer possesses a strong orbital Hall conductivity and the α-W layer features an orbital-to-spin conversion efficiency exceeding 90% because of the large orbit-spin diffusivity. By harnessing the giant orbital torque, we achieve a 28.7-picosecond switching and a five to eight-fold reduction in driving voltages over conventional spin-orbit torque magnetic memories. Our work bridges the critical gap between orbital effects and magnetic memory applications, significantly advancing the field of spintronics and orbitronics.

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Yuxuan Yao, Chen Xiao, Xiaobai Ning, Wenlong Cai, Xianzeng Guo, Zongxia Guo, Kailin Yang, Danrong Xiong, Zhengjie Yan, Shiyang Lu, Hongchao Zhang, Siyuan Cheng, Renyou Xu, Dinghao Ma, Chao Wang, Zhaohao Wang, Daoqian Zhu, Kaihua Cao, Hongxi Liu, Aurélien Manchon, Weisheng Zhao. 2025-04-11. Giant Orbital Torque-driven Picosecond Switching in Magnetic Tunnel Junctions. https://doi.org/10.1016/j.scib.2026.07.019

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