Steering Flexural Waves by Amplitude-Shift Elastic Metasurfaces

As 2D materials with subwavelength structures, elastic metasurfaces show remarkable abilities to manipulate waves at will through artificial boundary conditions. However, the application prospects of current may be restricted by their phase-only modulating boundaries. Herein, we present next generation additionally incorporating amplitude-shift modulation. A general theory for target wave fields steered is proposed modifying Huygens-Fresnel principle. examples, two concerning flexural in thin plates are carried out: one transform a cylindrical into Gaussian beam elaborating both amplitude and phase shifts, other focus incidence modulations only. These examples coincide well over theoretical calculations, numerical simulations experimental tests. This work underlie design complete control guided waves, extend more sophisticated applications, such as analog signal processing holographic imaging.