A fundamental study of the excitation of a Stoneley wave at a liquid–solid interface: Rayleigh angle and Gaussian beam incidence

Theoretical calculations show that near the Rayleigh angle the amplitude of the Stoneley wave generated by a homogeneous plane wave incident at the intersection between two liquids overlying a single solid has a local maximum. This maximum is very small compared with the one obtained for almost normal incidence at the mentioned intersection when the most efficient excitation occurs. The paper also presents numerical results for the generation of a Stoneley wave by means of an incident Gaussian beam. Finally, a very simple to interpret expression for the amplitude of the excited Stoneley wave is given.