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Imaging of a van der Waals spin-orbit torque system using spin ensembles in hBN

Zhang, Xi [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0000000257914829)·Zhou, Jingcheng [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0009000771967779)·Hu, Chaowei [University of Washington, Seattle, WA (United States)] (ORCID:0000000320710109)·Cai, PeiYu [University of Edinburgh (United Kingdom)] (ORCID:0000000239038941)·Deng, Kuangyin [University of California, Riverside, CA (United States)] (ORCID:0000000277995136)·Wang, Chuangtang [University of Michigan, Ann Arbor, MI (United States)] (ORCID:0009000062704837)·Agarwal, Nishkarsh [University of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000178936149)·Jin, Hanshang [University of California, Davis, CA (United States)]·Al-Matouq, Faris A. [Georgia Institute of Technology, Atlanta, GA (United States)]·Xu, Stelo [University of California, Davis, CA (United States)]·Trivedi, Roshan S. [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0009000229753340)·Li, Senlei [Georgia Institute of Technology, Atlanta, GA (United States)]·Rathi, Sumedh [Georgia Institute of Technology, Atlanta, GA (United States)]·Lu, Hanyi [Georgia Institute of Technology, Atlanta, GA (United States); University of California, San Diego, La Jolla, CA (United States)]·Jiang, Zhigang [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0000000198843337)·Taufour, Valentin [University of California, Davis, CA (United States)] (ORCID:0000000200249960)·Hovden, Robert [University of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000234038803)·Zhao, Liuyan [University of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000195123537)·Cheng, Ran [University of California, Riverside, CA (United States)] (ORCID:0000000301662172)·Xu, Xiaodong [University of Washington, Seattle, WA (United States)] (ORCID:0000000303482095)·Santos, Elton J. G. [University of Edinburgh (United Kingdom); Donostia International Physics Center (Spain)] (ORCID:0000000160655787)·Chu, Jiun-Haw [University of Washington, Seattle, WA (United States)] (ORCID:0000000162221210)·Du, Chunhui Rita [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0000000180637711)·Wang, Hailong [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0000000256178487)
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Abstract

Recently, optically active spin defects embedded in two-dimensional (2D) van der Waals (vdW) crystals have emerged as a transformative quantum sensing platform to explore cutting-edge materials science. Taking advantage of excellent solid-state integrability, this new class of spin defects can be readily arranged in nanoscale proximity to target materials, showing great promise for realizing in-situ quantum sensing of microscopic spin and charge behaviors in vdW heterostructures. Here we report hexagonal boron nitride-based quantum imaging of field-free deterministic magnetic switching and electric current distributions in an all-vdW spin-orbit torque (SOT) system. By visualizing variations of nanoscale magnetic stray field profile of room-temperature 2D magnet Fe 3 GaTe 2 under different SOT conditions, we show how the magnetic switching evolves from deterministic to stochastic behavior due to the interplay between spin orientations, anisotropy and Joule heating. Micromagnetic simulations rationalize our results well, revealing the role of field-like SOT in inhibiting thermal fluctuation driven stochastic switching and chaotic multi-domain competition. This understanding, which is otherwise difficult to access by conventional transport measurements, offers valuable insights into material design, testing, and performance evaluation of next-generation vdW spintronic devices.

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Imaging techniquesMagnetic devicesQuantum metrologySpintronicsTwo-dimensional materials

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Zhang, Xi [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0000000257914829), Zhou, Jingcheng [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0009000771967779), Hu, Chaowei [University of Washington, Seattle, WA (United States)] (ORCID:0000000320710109), Cai, PeiYu [University of Edinburgh (United Kingdom)] (ORCID:0000000239038941), Deng, Kuangyin [University of California, Riverside, CA (United States)] (ORCID:0000000277995136), Wang, Chuangtang [University of Michigan, Ann Arbor, MI (United States)] (ORCID:0009000062704837), Agarwal, Nishkarsh [University of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000178936149), Jin, Hanshang [University of California, Davis, CA (United States)], Al-Matouq, Faris A. [Georgia Institute of Technology, Atlanta, GA (United States)], Xu, Stelo [University of California, Davis, CA (United States)], Trivedi, Roshan S. [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0009000229753340), Li, Senlei [Georgia Institute of Technology, Atlanta, GA (United States)], Rathi, Sumedh [Georgia Institute of Technology, Atlanta, GA (United States)], Lu, Hanyi [Georgia Institute of Technology, Atlanta, GA (United States); University of California, San Diego, La Jolla, CA (United States)], Jiang, Zhigang [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0000000198843337), Taufour, Valentin [University of California, Davis, CA (United States)] (ORCID:0000000200249960), Hovden, Robert [University of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000234038803), Zhao, Liuyan [University of Michigan, Ann Arbor, MI (United States)] (ORCID:0000000195123537), Cheng, Ran [University of California, Riverside, CA (United States)] (ORCID:0000000301662172), Xu, Xiaodong [University of Washington, Seattle, WA (United States)] (ORCID:0000000303482095), Santos, Elton J. G. [University of Edinburgh (United Kingdom); Donostia International Physics Center (Spain)] (ORCID:0000000160655787), Chu, Jiun-Haw [University of Washington, Seattle, WA (United States)] (ORCID:0000000162221210), Du, Chunhui Rita [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0000000180637711), Wang, Hailong [Georgia Institute of Technology, Atlanta, GA (United States)] (ORCID:0000000256178487). 2026-06-10. Imaging of a van der Waals spin-orbit torque system using spin ensembles in hBN. https://doi.org/10.1038/s41467-026-74178-7

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