ABSTRACT
In Rayleigh waves, the longitudinal and shear motions are intimately coupled together, and they travel at a common velocity. This chapter starts with a detailed description of these waves on the surface of an isotropic solid in vacuum. Like much of acoustics, surface acoustic waves (SAWs) go back to Lord Rayleigh, and because of this, SAWs and Rayleigh waves are usually used synonymously. Rayleigh’s interest in the problem was brought about by his intuitive feeling that they could be a dominant acoustic signal triggered by earthquakes. Waves similar to Rayleigh waves on a free surface can propagate on the surface of a fluid-loaded solid. The existence of the Rayleigh dip can be explained in terms of attenuation of the surface wave. The displacement of bounded acoustic beams at the critical angle has its counterpart in optics, which in turn has a long and venerable history going back to Newton.
