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Manipulating the conversion phenomena among different wave modes is of great interest within the physics and engineering communities. In this Letter, a resonant elastic metamaterial is elaborately designed to achieve complete conversion from Lamb modes (A0 and S0) into the fundamental shear horizontal (SH0) mode. The key to achieving this interesting behavior resides in the design of a pillared perforated metamaterial, providing the strong coupling between the stub modes in shear resonant motion and the plate modes in the substrate medium. Both numerical modeling and experimental verification are conducted to validate the achievement of the mode conversion phenomenon.

We propose a simple method to design a wave trapping mechanism, referred to as an elastic open cavity, for shear horizontal waves using the concept of metasurfaces. Conventional open cavity designs have utilized bulk metamaterial media with negative refractive indices at certain frequencies. Here, we show that wave trapping can be attained depending on the incident angle with a suitable design and arrangement of several metasurfaces. This design strategy can be applied to waves with various incident angles and frequencies. We show that the incident angles and the number of metasurfaces are closely related. In addition, connections between the characteristic length of the metasurfaces and the resonance frequency are discussed. As an illustration, we theoretically derive the wave fields for an elastic open cavity with six metasurfaces. Numerical simulations based on the finite element calculations are performed to verify the correctness and consistency of the theory. Instead of using reflecting walls to localize energy, this wave trapping mechanism stores mechanical energy via constructive interference by guiding wave fronts that travel around closed contours. The demonstration of this concept could be a potential guide to design new energy harvesting devices.

Based on the effective-medium theory, the propagation of a shear horizontal (SH) wave in joined half-spaces composed of elastic metamaterials (EMMs) is investigated. From the dispersion relations, the effects of negative effective-medium parameters on the properties of a SH wave traveling near the interface are analyzed in detail. It is found that a SH wave can always appear and travel along the interface under specific effective-parameter combinations no matter whether the effective transverse wave velocity is imaginary or real. This is significantly different from the classical case (joined half-spaces composed of natural media), and the existence of these SH interfacial wave modes may have important impacts on EMM-based SH wave manipulation, especially wave isolation and object protection.

By discarding the quasi‐static approximation, this paper gives the exact solutions of a shear horizontal electromagneto‐acoustic surface wave mode in a class of piezoelectric media. As the wave speed is much less than the speed of light, the solution degenerates to the well‐known Bleustein–Gulyaev wave, or Maerfeld–Tournois wave. Taking into account both optical effect as well as the contribution from the rotational part of electric field, the solutions obtained here are not only valid for any wave speed range, but also provide accurate formulas to evaluate the acousto‐optic interaction due to the piezoelectricity.

Since surface transverse wave resonators are becoming increasingly used in high‐frequency electrical component applications, there is a pressing need for reliable simulation tools in this field. We develop analytical techniques for prediction of the resonant peaks of practical devices and apply them to the results of experiments in this laboratory and in others. The devices investigated are three‐grating structures composed of three arrays of metal strips or grooves on quartz substrates, which support a shear horizontal surface wave polarization. The outer gratings act as mirrors for the cavity resonance. The influence of the main design parameters on the resonator response is studied.

Inclined incidence of a shear horizontal elastic wave on a periodic structure of piezoelectric layers with metallized interfaces is considered. The layers are supposed to be made from the identical crystal of hexagonal symmetry but have alternating widths d1,d2. Due to the condition of fixed electropotential, each interface provides the reflection proportional to the parameter of electromechanical coupling q2. The interference of the reflected waves in the periodic structure causes the existence of the Bragg resonances in the reflection‐transmission spectrum so that ‖R‖max≊1 for a sufficiently large number of layers. Since q2≪1, the considered reflection spectrum exhibits some specific features such as high selectivity, modulation of the heights of the Bragg maximums depending on the value d1/(d1+d2), and the extinction effect.

We present a method for characterizing liquid‐solid phase transitions by using an acoustic shear horizontal (SH) plate mode sensor. The sensor consists of a Y‐cut quartz plate provided with suitable interdigital transducers on the lower surface. To study the temporal evolution of a phase transition, the liquid is deposited in a thin layer on the upper surface and the SH mode attenuation is observed as a function of time during a programed temperature change. With this sensor the theoretical time resolution is about 1 μs. Experimental results are presented for the liquid‐solid transition for deionized water, tap water, and 90%/10% mixture of tap water and ethanol, measured with an instrument time resolution of 50 ms.

We calculate the dispersion curves of surface acoustic waves of shear horizontal polarization propagating perpendicular to the grooves of a lamellar grating ruled on the surface of a cubic elastic medium. The calculation is based on a formulation of the problem that employs a coordinate‐dependent elastic modulus tensor and mass density, and is valid for an arbitrary ratio of the height of the ridges to the period of the grating. It is found that as this ratio increases the dispersion curve acquires additional, high‐frequency branches in addition to the one already known from earlier studies of this problem. An explanation for this result is proposed.

One-port surface acoustic wave resonators (SAW) were fabricated and characterized using Y-cut X propagating relaxor based ferroelectric single crystals of Pb(Mg1/3Nb2/3)O3-33%PbTiO3 and Pb(In1/3Nb2/3)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PIN-PMN-PT). The experimental results demonstrated ultrahigh electromechanical coupling factor K2 of ∼60% for shear horizontal SAW and a relatively strong spurious resonance due to the Rayleigh-type SAW which can be sufficiently suppressed with Au electrode of large thickness. Characteristics of temperature stability, sensitivity to DC bias voltage, and homogeneity for the two resonators were evaluated and compared. The results showed similar instability of domain structure, and PIN-PMN-PT resonators have better temperature stability, but inferior homogeneity compared to that of PMN-33%PT resonators.

In this research, shear horizontal (SH) surface acoustic wave (SAW) modes of interdigital transducer (IDT)/(100) AlN/(111) diamond propagated along the y-axis were theoretically analyzed and they exhibited excellent SH SAW properties. This is special for mode 0 where the K2 curve shows a maximum value (1.27%) at h/λ=0.28 and the velocity is 7496 m/s. The research results provide a predictable and theoretical basis for further application on high velocity SH SAW devices.