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arXiv · 1504.01374

Topological Phononic Crystals with One-Way Elastic Edge Waves

Pai Wang·Ling Lu·Katia Bertoldi
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Abstract

We report a new type of phononic crystals with topologically non-trivial bandgaps for both longitudinal and transverse polarizations, resulting in protected one-way elastic edge waves. In our design, gyroscopic inertial effects are used to break the time-reversal symmetry and realize the phononic analogue of the electronic quantum Hall effect. We investigate the response of both hexagonal and square gyroscopic lattices and observe bulk Chern number of 1 and 2, indicating that these structures support single and multi-mode edge elastic waves immune to back-scattering. These robust one-way phononic waveguides could potentially lead to the design of a novel class of surface wave devices that are widely used in electronics, telecommunication and acoustic imaging.

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Pai Wang, Ling Lu, Katia Bertoldi. 2015-04-04. Topological Phononic Crystals with One-Way Elastic Edge Waves. https://doi.org/10.1103/physrevlett.115.104302

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