Modelling of shear-horizontal-type surface acoustic waves and its application to COM-based device simulation

The paper is concerned with the propagation of shear horizontal surface waves (SHSW) in semi-infinite elastic media with vertically periodic continuous and/or discrete variation of material properties. The existence and spectral properties of the SHSW are shown to be intimately related to the shape of the properties variation profile. Generally, the SHSW dispersion branches represent randomly broken spectral intervals on the ( ω , k ) plane. They may, however, display a particular regularity in being confined to certain distinct ranges of slowness s = ω / k , which can be predicted and estimated directly from the profile shape. The SHSW spectral regularity is especially prominent when the material properties at the opposite edge points of a period are different. In particular, a unit cell can be arranged so that the SHSW exists within a single slowness window, narrow in the measure of material contrast between the edges, and does not exist elsewhere or vice versa. Explicit analysis in the ( ω , k ) domain is complemented and verified through the numerical simulation of the SH wave field in the time–space domain. The results also apply to a longitudinally periodic semi-infinite strip with a homogeneous boundary condition at the faces.

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Shear horizontal surface acoustic waves in a magneto-electro-elastic system

Journal of the Mechanical Behavior of Materials ◽

10.1515/jmbm-2015-0024 ◽

2016 ◽

Vol 25 (1-2) ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Shahin Eskandari ◽

Hossein M. Shodja

Keyword(s):

Power Series ◽

Shear Wave ◽

Half Space ◽

Wave Velocity ◽

Shear Wave Velocity ◽

Acoustic Waves ◽

Series Solution ◽

Surface Acoustic Waves ◽

Power Series Solution ◽

Shear Horizontal

AbstractPropagation of shear horizontal surface acoustic waves (SHSAWs) within a functionally graded magneto-electro-elastic (FGMEE) half-space was previously presented (Shodja HM, Eskandari S, Eskandari M. J. Eng. Math. 2015, 1–18) In contrast, the current paper considers propagation of SHSAWs in a medium consisting of an FGMEE layer perfectly bonded to a homogeneous MEE substrate. When the FGMEE layer is described by some special inhomogeneity functions – all the MEE properties have the same variation in depth which may or may not be identical to that of the density – we obtain the exact closed-form solution for the MEE fields. Additionally, certain special inhomogeneity functions with monotonically decreasing bulk shear wave velocity in depth are considered, and the associated boundary value problem is solved using power series solution. This problem in the limit as the layer thickness goes to infinity collapses to an FGMEE half-space with decreasing bulk shear wave velocity in depth. It is shown that in such a medium SHSAW does not propagate. Using power series solution we can afford to consider some FGMEE layers of practical importance, where the composition of the MEE obeys a prescribed volume fraction variation. The dispersive behavior of SHSAWs in the presence of such layers is also examined.

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Analytical Investigation of Surface Wave Characteristics of Piezoelectromagnetics of Class 6 mm

ISRN Applied Mathematics ◽

10.5402/2011/408529 ◽

2011 ◽

Vol 2011 ◽

pp. 1-8 ◽

Cited By ~ 6

Author(s):

Aleksey A. Zakharenko

Keyword(s):

Surface Wave ◽

Acoustic Waves ◽

Surface Acoustic Waves ◽

Transversely Isotropic ◽

Analytical Investigation ◽

Wave Characteristics ◽

Surface Wave Propagation ◽

Theoretical Investigations ◽

Derivatives Of ◽

Shear Horizontal

This short work copes with theoretical investigations of some surface wave characteristics for transversely isotropic piezoelectromagnetic composites of class 6 mm. In the composite materials, the surface Bleustein-Gulyaev-Melkumyan wave and some new shear-horizontal surface acoustic waves (SH-SAWs) recently discovered by the author can propagate. The phase velocities of the SH-SAWs can have complicated dependencies on the coefficient of the magnetoelectromechanical coupling (CMEMC) which depends on the electromagnetic constant of the composites. Therefore, the analytical finding of the first and second partial derivatives of the represents the main purpose of this study. It is thought that the results of this short letter can help for theoreticians and experimentalists working in the research arena of opto-acoustoelectronics to completely understand some problems of surface wave propagation in piezoelectromagnetics.

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