Room-temperature orbit-transfer torque enabling van der Waals magnetoresistive memories

Zhen-Cun Pan; Dong Li; Xing-Guo Ye; Zheng Chen; Zhao-Hui Chen; An-Qi Wang; Mingliang Tian; Guangjie Yao; Kaihui Liu; Zhi-Min Liao

doi:10.1016/j.scib.2023.10.008

Room-temperature orbit-transfer torque enabling van der Waals magnetoresistive memories

Sci Bull (Beijing). 2023 Nov 30;68(22):2743-2749. doi: 10.1016/j.scib.2023.10.008. Epub 2023 Oct 13.

Authors

Affiliations

¹ State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China.
² Academy for Advanced Interdisciplinary Studies, Peking University, Beijing 100871, China.
³ Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China.
⁴ Anhui Key Laboratory of Condensed Matter Physics at Extreme Conditions, High Magnetic Field Laboratory, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China; School of Physics and Optoelectronic Engineering, Anhui University, Hefei 230601, China; Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China.
⁵ State Key Laboratory for Mesoscopic Physics and Frontiers Science Center for Nano-optoelectronics, School of Physics, Peking University, Beijing 100871, China; Hefei National Laboratory, Hefei 230088, China. Electronic address: liaozm@pku.edu.cn.

PMID: 37872061
DOI: 10.1016/j.scib.2023.10.008

Abstract

The non-volatile magnetoresistive random access memory (MRAM) is believed to facilitate emerging applications, such as in-memory computing, neuromorphic computing and stochastic computing. Two-dimensional (2D) materials and their van der Waals heterostructures promote the development of MRAM technology, due to their atomically smooth interfaces and tunable physical properties. Here we report the all-2D magnetoresistive memories featuring all-electrical data reading and writing at room temperature based on WTe₂/Fe₃GaTe₂/BN/Fe₃GaTe₂ heterostructures. The data reading process relies on the tunnel magnetoresistance of Fe₃GaTe₂/BN/Fe₃GaTe₂. The data writing is achieved through current induced polarization of orbital magnetic moments in WTe₂, which exert torques on Fe₃GaTe₂, known as the orbit-transfer torque (OTT) effect. In contrast to the conventional reliance on spin moments in spin-transfer torque and spin-orbit torque, the OTT effect leverages the natural out-of-plane orbital moments, facilitating field-free perpendicular magnetization switching through interface currents. Our results indicate that the emerging OTT-MRAM is promising for low-power, high-performance memory applications.

Keywords: 2D magnetic materials; Magnetic tunnel junction; Magnetization switching; Magnetoresistive memory; Orbit-transfer torque; Spin-orbit torque.