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arXiv · 1708.06482

Pseudospins and topological effects of phonons in a Kekule lattice

Yizhou Liu·Chao-Sheng Lian·Yang Li·Yong Xu·Wenhui Duan
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Abstract

The search for exotic topological effects of phonons has attracted enormous interest for both fundamental science and practical applications. By studying phonons in a Kekulé lattice, we find a new type of pseudospins characterized by quantized Berry phases and pseudoangular momenta, which introduces various novel topological effects, including topologically protected pseudospin-polarized interface states and a phonon pseudospin Hall effect. We further demonstrate a pseudospin-contrasting optical selection rule and a pseudospin Zeeman effect, giving a complete generation-manipulation-detection paradigm of the phonon pseudospin. The pseudospin and topology-related physics revealed for phonons is general and applicable for electrons, photons and other particles.

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Yizhou Liu, Chao-Sheng Lian, Yang Li, Yong Xu, Wenhui Duan. 2017-12-13. Pseudospins and topological effects of phonons in a Kekule lattice. https://doi.org/10.1103/physrevlett.119.255901

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