Magnetization switching driven by magnon dissipation
Dong-Soo Han (Center for Spintronics, Korea Institute of Science and Technology (KIST), Seoul 02456, Republic of Korea)

Spintronics has emerged as a promising field for the development of energy-efficient magnetic memory and logic devices by controlling spin states in ferromagnets via spin-orbit coupling1,2. Efficient control of magnetization in ferromagnets is crucial for high-performance spintronic devices, and magnons have gained renewed interest as a potential avenue for achieving this goal with reduced Joule heating and minimized power consumption. In pursuit of this objective, Previous efforts have focused on optimizing magnon transport with minimal dissipation under the belief that dissipation hinders efficient magnetization control. In contrast, we present an unconventional approach that harnesses magnon dissipation for magnetization control instead of suppressing it. Our approach involves a heterostructure consisting of a ferromagnetic metal and an antiferromagnetic insulator, exploiting an intrinsic spin current within the ferromagnetic metal3,4. By combining a single ferromagnetic metal with an antiferromagnetic insulator that breaks spin transport symmetry while preserving charge transport symmetry, we achieve significant spin-orbit torques comparable to those observed in non-magnetic metals, enabling magnetization switching. Through systematic experiments and comprehensive analysis, we confirm that our findings arise from magnon dissipation within the AFI rather than external spin sources. These results provide novel insights into the mechanisms of spin current generation and dissipation, opening up new possibilities for developing energy-efficient spintronic devices.

Reference
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2. Shao, Q. et al. IEEE. Trans. Magn. 57, 1–39 (2021).
3. Hibino, Y. et al. Nat. Commun. 12, 6254 (2021).
4. Wang, W. et al. Nat. Nanotechnol. 14, 819–824 (2019).