Spin-orbit coupling driven handedness switching of magnons in altermagnets
Phys. Rev. B 113, 224403 – Published 1 June, 2026
DOI: https://doi.org/10.1103/hm4g-rl3y
Abstract
Altermagnets naturally host handedness-splitting magnon modes, providing a promising platform for low-dissipation and ultrafast handedness-based computing. However, achieving precise and active control over the magnon handedness remains a challenge. Here, we propose a mechanism for the electrical switching of magnon handedness in altermagnets via interfacial Rashba spin-orbit coupling (SOC), which is free of tuning external excitation fields. For an in-plane polarized magnetic ground state, SOC induces a splitting effect that inherently competes with the altermagnetism. Strong-coupling perturbation expansion reveals that this competition originates microscopically from a dynamically induced next-nearest-neighbor Dzyaloshinskii-Moriya interaction. This destructive interference leading to a macroscopic momentum-space reversal of both the electronic spin splitting and the magnon handedness splitting. Consequently, tuning the SOC strength enables a deterministic switching of the dominant precessional handedness under fixed resonance conditions. We further propose an experimental setup utilizing an altermagnet/insulator heterostructure to validate this mechanism. Our work establish a pathway toward the efficient electrical manipulation of magnon excitations, facilitating the development of handedness-based magnonic devices.
