Resonant excitation of waveguide SH acoustic modes in a piezoelectric plate

An excitation of waveguide SH acoustic modes is studied for a layer piezoelectrically coupled with a substrate through a narrow gap. The idea of the method is based on a resonance reflection of plane waves occurring in the substrate close to the tracing speeds of the spectrum of waveguide SH eigenwaves in the layer. Such reflections in the substrate are accompanied by the waveguide components in the layer with rather large amplitudes proportional to the inverse coefficient of electro-mechanical coupling. The shape of resonant peaks of excitation is theoretically studied. The physical limitations for the parameters of resonance are discussed.