Tunable Acoustic Valley-Hall Edge States in Reconfigurable Phononic Elastic Waveguides

Abstract

This study investigates the occurrence of acoustic topological edge states in a 2D phononic elastic waveguide due to a phenomenon that is the acoustic analogue of the quantum valley Hall effect. We show that a topological transition takes place between two lattices having broken space inversion symmetry due to the application of a tunable strain field. This condition leads to the formation of gapless edge states at the domain walls, as further illustrated by the analysis of the bulk-edge correspondence and of the associated topological invariants. Although time reversal symmetry is still intact in these systems, the edge states are topologically protected when inter-valley mixing is either weak or negligible. Interestingly, topological edge states can also be triggered at the boundary of a single domain if boundary conditions are properly selected. We also show that the static modulation of the strain field allows tuning the response of the material between the different supported edge states.

9 pages, 13 figures

References in corpus (12)

• The electronic properties of graphene
• Topological Acoustics
• Analogs of quantum Hall effect edge states in photonic crystals
• Observation of phononic helical edge states in a mechanical 'topological insulator'
• Observation of topological valley transport of sound in sonic crystals
• Topological confinement in bilayer graphene
• Valley Vortex States in Sonic Crystals
• Edge states in Graphene: from gapped flat band to gapless chiral modes
• Edge waves in plates with resonators: An elastic analogue of the quantum valley Hall effect
• Observation of topological valley modes in an elastic hexagonal lattice
• Electronic Highways in Bilayer Graphene
• Valley-Hall Kink and Edge States in Multilayer Graphene

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