Valley Phenomena and Corner State Realization in Bilayer Hexagonal Phononic Crystals

doi:10.13438/j.cnki.jdzk.2025.05.007

Abstract

Abstract: Benefiting from valley-selective excitation and suppressed acoustic backscattering in valley topological insulators,we designed a mirror-symmetric bilayer hexagonal phononic crystal.Breaking spatial symmetry by adjusting the scatterers' orientation induces valley states.Numerical simulations show different valley topological phases emerge under varying scatterer angles,enabling selective path transport.Furthermore,constructing a triangular supercell with two valley topological phases in the bilayer hexagonal phononic crystal yields two sets of triangular corner states.

Key words: bilayer hexagonal phononic crystals, valley topology, corner state

LIU Fang, WANG Jiahao, KONG Peng, ZHAO Heping, DENG Ke. Valley Phenomena and Corner State Realization in Bilayer Hexagonal Phononic Crystals[J]. Journal of Jishou University(Natural Sciences Edition), 2025, 46(5): 45-52.

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