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arXiv · 2104.13161

Observation of dislocation-induced topological modes in a three-dimensional acoustic topological insulator

Haoran Xue·Ding Jia·Yong Ge·Yi-jun Guan·Qiang Wang·Shou-qi Yuan·Hong-xiang Sun·Y. D. Chong·Baile Zhang
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Abstract

The interplay between real-space topological lattice defects and the reciprocal-space topology of energy bands can give rise to novel phenomena, such as one-dimensional topological modes bound to screw dislocations in three-dimensional topological insulators. We obtain direct experimental observations of dislocation-induced helical modes in an acoustic analog of a weak three-dimensional topological insulator. The spatial distribution of the helical modes is found through spin-resolved field mapping, and verified numerically by tight-binding and finite-element calculations. These one-dimensional helical channels can serve as robust waveguides in three-dimensional media. Our experiment paves the way to studying novel physical modes and functionalities enabled by topological lattice defects in three-dimensional classical topological materials.

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Haoran Xue, Ding Jia, Yong Ge, Yi-jun Guan, Qiang Wang, Shou-qi Yuan, Hong-xiang Sun, Y. D. Chong, Baile Zhang. 2021-04-27. Observation of dislocation-induced topological modes in a three-dimensional acoustic topological insulator. https://doi.org/10.1103/physrevlett.127.214301

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