Propagation of the Bleustein-Gulyaev waves in a functionally graded transversely isotropic electro-magneto-elastic half-space

Bleustein-Gulyaev (B-G) waves in a functionally graded transversely isotropic electro-magneto-elastic half-space, in which all parameters exponentially change along the depth direction, are investigated, and the dispersion equations with respect to the phase velocity for electromagnetically open and shorted conditions are obtained. The B-G waves are dispersive because of the inhomogeneity of the material, which is different from a pure substrate. The graded coefficient exhibits different effects on the B-G waves at different electromagnetic circumstances. With the intervention of the functionally graded material, the electro-magneto-mechanical coupling factor can be improved and the penetration depth of the B-G waves can be decreased. The results can be used in the design of high-performance surface acoustic wave devices. (C) 2012 Elsevier Masson SAS. All rights reserved.