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arXiv · 2203.13361

Phonon Chirality Induced by Vibronic-Orbital Coupling

Yun-Yi Pai·Claire E. Marvinney·Liangbo Liang·Ganesh Pokharel·Jie Xing·Haoxiang Li·Xun Li·Michael Chilcote·Matthew Brahlek·Lucas Lindsay·Hu Miao·Athena S. Sefat·David Parker·Stephen D. Wilson·Benjamin J. Lawrie
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Abstract

The notion that phonons can carry pseudo-angular momentum has become popular in the last decade, with recent research efforts highlighting phonon chirality, Berry curvature of phonon band structure, and the phonon Hall effect. When a phonon is resonantly coupled to a crystal electric field excitation, a so-called vibronic bound state forms. Here, we observe angular momentum transfer of $\delta$Jz = $\pm$1$\hbar$ between phonons and an orbital state in a vibronic bound state of a candidate quantum spin liquid. This observation has profound implications for the engineering of phonon band structure topology through chiral quasiparticle interactions.

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Yun-Yi Pai, Claire E. Marvinney, Liangbo Liang, Ganesh Pokharel, Jie Xing, Haoxiang Li, Xun Li, Michael Chilcote, Matthew Brahlek, Lucas Lindsay, Hu Miao, Athena S. Sefat, David Parker, Stephen D. Wilson, Benjamin J. Lawrie. 2022-03-19. Phonon Chirality Induced by Vibronic-Orbital Coupling. https://arxiv.org/abs/2203.13361

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