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Modern society is supported by various technologies such as AI (artificial intelligence), IoT (internet of things), 5G (fifth generation technology standard for cellular networks), etc. Indispensable key components within these technologies are, of course sensors that detect and monitor various physical, chemical, and biological parameters. To monitor mechanical movements, such as vibration and bending, piezoelectric materials can effectively be used. Piezoelectricity is a phenomenon that is observed in a certain kind of dielectric materials and many academic papers in scientific conferences and journals have been devoted to this phenomenon, including publications of IEEE DEI Society [1, 2]. [ABSTRACT FROM AUTHOR]

The author reflects on the 5th Asian Meeting on Ferroelectrics (AMF-5) that was held at Tokyo University of Science (TUS) on September 3-7, 2006 in Noda, Japan. They stress that the meeting was organized by the Asian Ferroelectric Association (AFA) which includes the presentation of 300 abstracts and 240 contributions as well as workshop that deals to the various issues on ferroelectrics. The authors points out that discussions on dielectrics and piezoelectrics were given.

A structure with a ribbon-shaped metal thin film on a highly coupled anisotropic piezoelectric substrate acts to concentrate the acoustic wave energy into the region with the thin film. A device making use of the nonlinear interaction of the surface acoustic waves propagating in opposite directions on this Δv/v waveguide is the surface acoustic wave convolver. However, a theoretical analysis on its efficiency is not sufficient. In the present research, the guided wave characteristics of this Δv/v waveguide are derived accurately so that the nonlinear components generated on the waveguide are computed. The generation efficiency of the surface acoustic wave at the second harmonic generated from this mechanism in the direction orthogonal to the waveguide is analyzed theoretically. The conversion efficiency of the split waveguide-type convolver proposed previously by the authors can be derived quantitatively so that the evaluation of the surface acoustic wave nonlinear device becomes possible. [ABSTRACT FROM AUTHOR]

In-plane vibration in rectangular plates of piezo-electric ceramics which were polarized along the direction of plate thickness was investigated by two-dimensional transient analysis. In this analysis, it was assumed that both the top and bottom surfaces of the rectangular ceramic plates were electroded entirely and the four-edge surfaces were not constrained. The spatial network method was employed for numerical analyses. Transient were evaluated numerically first for the cases where stepwise input were applied to square plates. In-plane wave motion and displacements of free edges were calculated. The results indicate the following behaviors: 1) a longitudinal wave is created at the free edge and propagates along the surface of the plate: 2) a part of the longitudinal wave is transformed to a shear wave at a free boundary parallel to the direction of the wave propagation; and 3) these two waves experience repeated reflections at the free boundaries and thus form a complicated vibration. Transient responses of a rectangular ceramic plate were analyzed next. Prior to the analysis, the vibratory behaviors of the rectangular plate were predicted approximately based on the results for the square plate. The detailed numerical analyses performed could confirm the validity of the predictions. [ABSTRACT FROM AUTHOR]