Surface Acoustic Waves Propagation at Lossy Metasurfaces: Experimental and Theoretical Characterization of Complex Dispersion Relations

2016

International audience; While metasurfaces properties are known to govern the dispersion relation of Surface Acoustic Wave (SAW) that mimics surface plasmon phenomena, little attention has been paid to the effects of micro-structural dissipation on that dispersion relation. Here we report the experimental and theoretical characterization of both SAW propagation and attenuation in the presence of a lossy metasurface. The latter consists of quarter-wavelength resonators embedded in a rigid board and arranged periodically in a square lattice. Complex SAW wavenumbers are retrieved experimentally using a spatial Laplace Transform, and experimental results are compared with those from an analytic…