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arXiv · 2001.06205

Discovering topological surface states of Dirac points

Hengbin Cheng·Yixin Sha·Rongjuan Liu·Chen Fang·Ling Lu
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Abstract

Dirac materials, unlike the Weyl materials, have not been found in experiments to support intrinsic topological surface states, as the surface arcs in existing systems are unstable against symmetry-preserving perturbations. Utilizing the proposed glide and time-reversal symmetries, we theoretically design and experimentally verify an acoustic crystal of two frequency-isolated three-dimensional Dirac points with $Z_2$ monopole charges and four gapless helicoid surface states.

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Hengbin Cheng, Yixin Sha, Rongjuan Liu, Chen Fang, Ling Lu. 2020-01-17. Discovering topological surface states of Dirac points. https://doi.org/10.1103/physrevlett.124.104301

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