Energy-Efficient Single Layer Spin Hall Nano-Oscillators Driven by Berry Curvature
Journal article, 2025
Spin Hall nano-oscillators (SHNOs) are emerging spintronic oscillators with significant potential for technological applications, including microwave signal generation, and unconventional computing. Despite their promising applications, SHNOs face various challenges, such as high energy consumption and difficulties in growing high-quality thin film heterostructures with clean interfaces. Here, single-layer topological magnetic Weyl semimetals open a possible solution as they possess both intrinsic ferromagnetism and a large spin-orbit coupling due to their topological properties. However, producing such high-quality thin films of magnetic Weyl semimetals that retain their topological properties and Berry curvature remains a challenge. We address these issues with high-quality single-layer epitaxial ferromagnetic Co2MnGa Weyl semimetal thin film-based SHNOs. We observe a giant spin Hall conductivity, σSHC = (6.08 ± 0.02) × 105 (ℏ/2e) Ω-1 m-1, which is an order of magnitude higher than previous reports. Theoretical calculations corroborate the experimental results with a large intrinsic spin Hall conductivity due to presence of a strong Berry curvature. Further, self spin-orbit torque driven magnetization auto-oscillations are demonstrated for the first time, at an ultralow threshold current density of Jth = 6.2 × 1011 A m-2. These findings indicate that magnetic Weyl semimetals have tremendous application potential for developing energy-efficient spintronic devices.
magnetic Weyl semimetal
microfocused Brillouin light scattering
magnetization auto-oscillations
intrinsic spin−orbit torque
spin Hall nano-oscillator
Berry curvature
Author
Lakhan Bainsla
University of Gothenburg
Indian Institute of Technology
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Yuya Sakuraba
National Institute for Materials Science (NIMS)
Akash Kumar
University of Gothenburg
Tohoku University
Avinash Kumar Chaurasiya
University of Gothenburg
Keisuke Masuda
National Institute for Materials Science (NIMS)
Nattamon Suwannaharn
National Institute for Materials Science (NIMS)
Ahmad Awad
University of Gothenburg
Tohoku University
Nilamani Behera
University of Gothenburg
Roman Khymyn
University of Gothenburg
Taisuke Sasaki
National Institute for Materials Science (NIMS)
Saroj Prasad Dash
Chalmers, Microtechnology and Nanoscience (MC2), Quantum Device Physics
Johan Åkerman
Tohoku University
University of Gothenburg
ACS Nano
1936-0851 (ISSN) 1936-086X (eISSN)
Vol. 19 192D Heterostructure Non-volatile Spin Memory Technology (2DSPIN-TECH)
European Commission (EC) (EC/HE/101135853), 2023-12-01 -- 2026-11-30.
2D material-based technology for industrial applications (2D-TECH)
VINNOVA (2019-00068), 2020-05-01 -- 2024-12-31.
VINNOVA (2024-03852), 2023-11-01 -- 2029-12-31.
GKN Aerospace Sweden (2D-tech), 2021-01-01 -- 2024-12-31.
2Dimensional van der Waals Spin-Orbit Torque Technology
Swedish Research Council (VR) (2021-05925), 2021-12-01 -- 2024-11-30.
Driving Forces
Sustainable development
Subject Categories (SSIF 2025)
Condensed Matter Physics
DOI
10.1021/acsnano.5c02048