Gap surface waves in a system of two elastic superconducting semispaces separated by a narrow gap

This paper deals with the magnetoelastic interactions for a structure consisting of two elastic current carrying superconducting substrates, separated by a gap (vacuum). The two elastic substrates, which have no acoustic contacts, are coupled by a magnetic field generated by the deformations of the substrates. The surface magnetoelastic waves of Rayleigh type, decaying exponentially with distance from substrates surfaces, are studied. For a plane harmonic wave the dispersion equation is derived and solved to obtain the coupled wave frequencies. The magnetomechanical coupling effects are investigated in detail and simulations show that the magnetoelastic coupling effect is quite significant when the gap relative thickness is rather small. The existence of two surface gap waves with two different velocities is shown. In superconducting media the constitutive relations of magnetic field and electrical current of primary nondeformed state are given by means of London's equation