Fig. 3: Unidirectional and backscattering-immune phonon transport through CESs.
From: General duality and magnet-free passive phononic Chern insulators
a, b CESs excited by a point source at the interface between a phononic Chern insulator and air above and below the large scatterer (gray region), when the bulk has a negative doping charge density (q < 0). c The CES propagates along the opposite direction when the bulk doping charge density is positive (q > 0). The blue-red color scheme represents the out-of-plane velocity vz.
