Demonstration of shear waves, Lamb waves, and Rayleigh waves by mode conversion

When a plane elastic wave strikes an interface between two different media, mode conversion occurs. The reflected and refracted waves may consist of both longitudinal waves and shear waves. Under some circumstances, Rayleigh surface waves and Lamb waves can also be excited. A simple experiment which can be demonstrated in the classroom is introduced here to show that shear waves, Rayleigh waves, and Lamb waves can be easily generated and observed by means of mode conversion.