Fig. 3: Unidirectional and tunable canalization.
From: All-angle unidirectional flat-band acoustic metasurfaces
a, c, e The schematics on the bilayer moiré system with three levels of symmetry breaking: none, in-plane, or both in-plane and out-of-plane. b Pressure field and Fourier spectra at different θ. d Pressure field and Fourier spectra at different β. f Pressure field and Fourier spectra at the same γ and different β. The green curves are the dispersion curves calculated using the theoretical bilayer model. The dashed curves indicate the dispersion curves of the upper and lower metasurfaces. The simulations are frequency domain simulations. The simulated domains in (b, d, f) are the air surrounding the metasurface, with the metasurface structure modeled as a hard boundary.
