TWO DIMENSIONAL SAW GREEN'S FUNCTIONS FOR SURFACE EXCITATION OF PIEZOELECTRIC CRYSTAL

Recently we have investigated two-dimensional generalized Green's functions for surface excitation in a half space of piezoelectric crystal.In this paper,the SAW part of generalized Green's functions are discussed in detail.On using the method of stationary phase,the asymptotic behavier of SAW far fields is obtained.But,since such asymptotic solutions near the turning points of slowness curve fail,the general asymptotic solutions expressed by a varied Airy function are developed.And the joining problem of solutions near the turning points can be resolved.
Finally,for the Y-cut LiNbO₃,the components and the power flux density of SAW Green's function at far fields are numerically calculated.The results show that focusing phenomena at the Z direction Y-cut LiNbO₃ is presented.