Topological phononics

Zeguo Chen; Tiantian Zhang; Xulong Wang; Jiangxu Li; Zhi-Kang Lin; Feng Gao; Li-Wei Wang; Yizhou Liu; Qi Wang; Xiujuan Zhang; Guancong Ma; Xingqiu Chen; Minghui Lu; Yanfeng Chen; Jian-Hua Jiang

arXiv · 2605.20900

Topological phononics

Zeguo Chen·Tiantian Zhang·Xulong Wang·Jiangxu Li·Zhi-Kang Lin·Feng Gao·Li-Wei Wang·Yizhou Liu·Qi Wang·Xiujuan Zhang·Guancong Ma·Xingqiu Chen·Minghui Lu·Yanfeng Chen·Jian-Hua Jiang

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Abstract

Topological phononics extends the foundational concepts of topological condensed matter physics to the realm of lattice vibrations and classical mechanical waves, unlocking robust, defect-immune states and phenomena beyond the reach of conventional phononic engineering. This review provides a unified, systematic framework for understanding topological phonons across natural and artificial systems, spanning solid-state materials, acoustic/mechanical metamaterials, and non-Hermitian platforms. We cover the core theoretical principles -- from Berry curvature and symmetry-protected topological invariants to bulk-boundary correspondence -- alongside experimental advances in probing topological phonon states via inelastic scattering and momentum-resolved techniques for solid-state phonons as well as pump-probe measurements in acoustic/mechanical metamaterials. Key topics include Weyl/Dirac/nodal-line phonons in crystalline solids, symmetry-engineered topological phases in metamaterials, non-Hermitian effects (exceptional points, skin effect), and emergent directions such as Floquet engineering, synthetic dimensions, and real-space topological textures (skyrmions, merons). We also highlight technological applications in robust waveguides, on-chip surface-acoustic-wave devices, and acoustofluidics, while outlining future challenges and opportunities in quantum phononics, nonlinear topological phenomena, and interdisciplinary integration with photonics and electronics. This review serves as a comprehensive guide across physics, materials science, and engineering, bridging fundamental theory with cutting-edge experiments and innovations in topological phononics.

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Zeguo Chen, Tiantian Zhang, Xulong Wang, Jiangxu Li, Zhi-Kang Lin, Feng Gao, Li-Wei Wang, Yizhou Liu, Qi Wang, Xiujuan Zhang, Guancong Ma, Xingqiu Chen, Minghui Lu, Yanfeng Chen, Jian-Hua Jiang. 2026-05-20. Topological phononics. https://arxiv.org/abs/2605.20900

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