Second-harmonic generation in sound beams reflected from, and transmitted through, immersed elastic solids.

Second-harmonic generation in sound beams reflected from and transmitted through thick isotropic elastic solids is investigated experimentally. Measurements of diffraction patterns are compared with a theoretical model based on integral solutions for harmonic generation in sound beams. The solutions are connected by classical linear theory for reflection and transmission at fluid-solid interfaces. Nonspecular phenomena associated with rapid phase variations near critical angles are accurately described. The principal restriction is that the solid is sufficiently thick that internal reflections may be ignored.