Figure 5. The simulated and measured pressure amplitude distributions of the one-way interface state.

(a) The simulated pressure amplitude distribution for the interface state after the lattice is dislocated by half a lattice constant D. The pseudo-spin-up interface state is excited from the lower arm of the left U-shape waveguide and propagates unidirectionally to the right output. If we excite the wrong spin component at the input port, we will obtain a bulk state instead of an interface state (see Supplementary Fig. 9). (b) The measured sound energy distribution for this one-way interface state. The operating frequency of sound is 7.46 kHz.