Elastic Weyl Points and Surface Arc States in Three-Dimensional Structures

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Elastic Weyl Points and Surface Arc States in Three-Dimensional Structures

Xiaotian Shi, Rajesh Chaunsali, Feng Li, and Jinkyu Yang

Phys. Rev. Applied 12, 024058 – Published 28 August 2019

Abstract

The study of Weyl points in electronic systems has inspired much recent research in classical systems such as photonic and acoustic lattices. Here we show how Weyl physics can also inspire the design of novel elastic structures. We construct a single-phase three-dimensional structure, an analog of the $A A$ -stacked honeycomb lattice, and predict the existence of Weyl points with opposite topological charges ( $\pm 1$ ), elastic Fermi arcs, and the associated gapless topologically protected surface states. We apply full-scale numerical simulations on the elastic three-dimensional structure and present a clear visualization of topological surface states that are directional and robust. Such designed lattices can pave the way for novel vibration control and energy harvesting on structures that are ubiquitous in many engineering applications.

Received 16 May 2019
Revised 5 August 2019

DOI:https://doi.org/10.1103/PhysRevApplied.12.024058

Physics Subject Headings (PhySH)

Acoustic metamaterials Fermi surface Mechanical & acoustical properties Surface states Symmetry protected topological states Topological phases of matter

Weyl semimetal

Surface acoustic wave

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Xiaotian Shi¹, Rajesh Chaunsali^1,2, Feng Li³, and Jinkyu Yang^1,*

¹Aeronautics and Astronautics, University of Washington, Seattle, Washington 98195, USA
²LAUM, CNRS, Le Mans Université, Avenue Olivier Messiaen, 72085 Le Mans, France
³School of Physics and Optoelectronic Technology, South China University of Technology, Guangzhou, 510640 Guangdong, China