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arXiv · 2411.03879

Chiral Phonons Arising From Chirality-Selective Magnon-Phonon Coupling

Markus Weißenhofer·Philipp Rieger·M. S. Mrudul·Luca Mikadze·Ulrich Nowak·Peter M. Oppeneer
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Abstract

Chiral phonons are desirable for applications in spintronics but their generation and control remains a challenge.Here we demonstrate the emergence of truly chiral phonons from selective magnon-phonon coupling in inversion-symmetric magnetic systems. Considering bcc Fe as example, we quantitatively calculate hybridized magnon-phonon quasiparticle states across the entire Brillouin zone utilizing first-principles calculations. Our findings challenge conventional magneto-elastic interpretations and reveal finite zero-point phonon angular momentum and strong anomalous thermal Hall responses linked to finite (spin) Berry curvatures. Our results further establish that the existence of chiral phonons, particularly along high-symmetry directions, is common in many magnetic materials, offering promising avenues for novel spintronic and phononic devices.

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Markus Weißenhofer, Philipp Rieger, M. S. Mrudul, Luca Mikadze, Ulrich Nowak, Peter M. Oppeneer. 2024-11-06. Chiral Phonons Arising From Chirality-Selective Magnon-Phonon Coupling. https://doi.org/10.1103/j7bs-2zbx

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