Rectification of elastic waves in a thin plate

Abstract

We propose a rectifier of elastic waves in a thin plate, which is made of an elastically isotropic material containing a periodic array of triangular holes as scatterers, and demonstrate numerically that it works both for the symmetric and anti-symmetric Lamb waves as well as shear horizontal waves. The rectification is caused by the geometric effects on wave scattering due to the asymmetric scatterers, while the interplay between the mode conversion and interference effects among the scattered waves owing to the periodic arrangement of scatterers complicates it. The mechanism makes it possible to rectify the typical elastic waves in the system above the threshold frequency corresponding to the wavelength equivalent to the periodicity of scatterers.