Surface-Acoustic-Wave Computing of the Grover Quantum Search Algorithm with Metasurfaces

Wave-based computing has attracted extensive attention recently due to the benefits of parallel processing. In particular, several acoustic wave computing devices have been demonstrated to carry out classical algorithms and mathematical operations. Here, we extend acoustic wave computing to simulate a quantum algorithm, by proposing an integrated acoustic gradient metasurface system supporting spoof surface acoustic waves to implement the Grover quantum search algorithm. We show that this integrated metadevice can achieve a designed subdiffraction and transmission phase, which can be used to simulate operations used in a quantum algorithm, such as the Hadamard transformation and the inverse about the average. Numerical simulations demonstrate promising searching abilities of this device, including a quadratic speedup over classical algorithms and subwavelength searching accuracy. We anticipate that our results will inspire alternative design schemes for on-chip integrated metadevices for more quantum-inspired acoustic analog computations.