Polarization-dependent and valley-protected Lamb waves in asymmetric pillared phononic crystals

  title={Polarization-dependent and valley-protected Lamb waves in asymmetric pillared phononic crystals},
  author={Wei Wang and Bernard Bonello and Bahram Djafari-Rouhani and Yan Pennec},
  journal={Journal of Physics D: Applied Physics},
We present the realization of the topological valley-protected zero-order antisymmetric (A0) or symmetric (S0) and zero-order shear-horizontal (SH0) Lamb waves at different domain walls based on topologically distinct asymmetric double-sided pillared phononic crystals. The elastic periodic structures have either the triangular or the honeycomb symmetry and give rise to a double-negative branch in the dispersion curves. By artificially folding the doubly negative branch, a degenerate Dirac cone… 

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