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Shear horizontal (SH) wave propagation in finite graded piezoelectric layered media is investigated by transfer matrix method. Different from the previous studies on SH wave propagation in completely periodic layered media, calculations on band structure and transmission in this paper show that the graded layered media possess very large band gaps. Harmonic wave simulation by finite element method (FEM) confirms that the reason of bandwidth enlargement is that waves within the band gap ranges are spatially enhanced and stopped by the corresponding graded units. The study suggests that the graded structure possesses the property of manipulating elastic waves spatially, which shows potential applications in strengthening energy trapping and harvesting.

In this paper, through numerical simulation of the first order shear horizontal guided waves propagation in a homogeneous tapered plate, we have realized sound unidirectional transmission based on the mode conversion mechanism. We also find that the contrast transmission ratio of unidirectional transmission is highly influenced by the slope angle of tapered edge. And the working frequency range of the asymmetric transmission can be easily controlled by the height of tapered surface or the thickness of slab. This asymmetric system shows potentially significant applications in various sound devices.

Oblique incidence of a shear horizontal elastic wave on a periodic structure of identical piezomagnetic layers, separated by thin superconductive coatings, is considered. The Bragg resonance of reflection arising due to the s state on the interfaces is analyzed. It is shown that for a sufficiently large number of layers the reflection coefficient R may change from zero to R ≈1 for the n-s transition.

Second-order nonlinearity causes acoustic waves of shear-horizontal polarization to couple to sagittal components of the displacement field. This coupling is usually nonresonant and merely alters the effective nonlinearity parameter in the equation governing the nonlinear evolution of guided acoustic waves which, in the linear limit, are of purely shear-horizontal polarization. Using plate modes as an example, we demonstrate how in the neighbourhood of a resonance of a fundamental wit its second harmonic, the effect of second-order nonlinearity greatly exceed those of the third-order nonlinearity which are the dominant nonlinear effects when only shear-horizontal displacements are considered.

Long-wavelength, low-frequency shear-horizontal surface waves are found to exist along 〈100〉, but not 〈110〉, directions of propagation on the (001) face for a simple but fairly realistic model of monatomic body-centered cubic crystals. This domain of existence contrasts with that found previously on the (001) face of monatomic simple cubic and both monatomic and rocksalt face-centered cubic structures, where such waves exist along 〈110〉, but not 〈100〉.

A connection is made between (1) the result of elasticity theory that shear-horizontal (SH) surface waves cannot exist on a cubic (001) surface and (2) the result of a number of lattice studies of surface modes in thin films to the effect that SH surface waves do appear to exist along [110] for large, but finite wavelength λ. The SH surface wave frequency departs from the bulk band edge as λ-3 and the localization depth is proportional to λ2.