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Twisted photonic Weyl meta-crystals and aperiodic Fermi arc scattering.

ABSTRACT: As a milestone in the exploration of topological physics, Fermi arcs bridging Weyl points have been extensively studied. Weyl points, as are Fermi arcs, are believed to be only stable when preserving translation symmetry. However, no experimental observation of aperiodic Fermi arcs has been reported so far. Here, we continuously twist a bi-block Weyl meta-crystal and experimentally observe the twisted Fermi arc reconstruction. Although both the Weyl meta-crystals individually preserve translational symmetry, continuous twisting operation leads to the aperiodic hybridization and scattering of Fermi arcs on the interface, which is found to be determined by the singular total reflection around Weyl points. Our work unveils the aperiodic scattering of Fermi arcs and opens the door to continuously manipulating Fermi arcs.

SUBMITTER: Wang H

PROVIDER: S-EPMC10948390 | biostudies-literature | 2024 Mar

REPOSITORIES: biostudies-literature

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Twisted photonic Weyl meta-crystals and aperiodic Fermi arc scattering.

Wang Hanyu H Xu Wei W Wei Zeyong Z Wang Yiyuan Y Wang Zhanshan Z Cheng Xinbin X Guo Qinghua Q Shi Jinhui J Zhu Zhihong Z Yang Biao B

Nature communications 20240318 1

As a milestone in the exploration of topological physics, Fermi arcs bridging Weyl points have been extensively studied. Weyl points, as are Fermi arcs, are believed to be only stable when preserving translation symmetry. However, no experimental observation of aperiodic Fermi arcs has been reported so far. Here, we continuously twist a bi-block Weyl meta-crystal and experimentally observe the twisted Fermi arc reconstruction. Although both the Weyl meta-crystals individually preserve translatio ...[more]

PMID: 38499579

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