Jin-Xi Liu

Bio: Jin-Xi Liu is an academic researcher from Shijiazhuang Railway Institute. The author has contributed to research in topics: Piezoelectricity & Piezoelectric coefficient. The author has an hindex of 18, co-authored 86 publications receiving 1097 citations.

Effects of surface piezoelectricity and nonlocal scale on wave propagation in piezoelectric nanoplates

Abstract: In this paper, the dispersion characteristics of elastic waves propagating in a monolayer piezoelectric nanoplate is investigated with consideration of the surface piezoelectricity as well as the nonlocal small-scale effect. Nonlocal electroelasticity theory is used to derive the general governing equations by introducing an intrinsic length, and the surface effects exerting on the boundary conditions of the piezoelectric nanoplate are taken into account through incorporation of the surface piezoelectricity model and the generalized Young–Laplace equations. The dispersion relations of elastic waves based on the current formulation are obtained in an explicit closed form. Numerical results show that both the nonlocal scale parameter and surface piezoelectricity have significant influence on the size-dependent properties of dispersion behaviors. It is also found that there exists an escape frequency above which the waves may not propagate in the piezoelectric plate with nanoscale thickness.

Interfacial shear horizontal waves in a piezoelectric-piezomagnetic bi-material

Abstract: The propagation of an interfacial shear horizontal (SH) wave is studied in two bonded semi-infinite materials, one piezoelectric and the other piezomagnetic. Both materials are hexagonal (6 mm) crystals. The dispersion relation is given in an explicit form. Based on the obtained dispersion relationship, conditions for the existence of interfacial SH waves are discussed in detail.

Propagation of Rayleigh-type surface waves in a transversely isotropic piezoelectric layer on a piezomagnetic half-space

Abstract: Propagation of Rayleigh-type surface waves in a piezoelectric-piezomagnetic layered half-space is investigated. The materials are assumed to be transversely isotropic crystals. The dispersion relations have been numerically derived and computed by considering the coupling piezoelectric and piezomagnetic behaviors. The phase velocities are obtained for four kinds of electric-magnetic boundary conditions at the free surface. The variations of mechanical displacements, electric and magnetic potentials along the thickness direction of the layer are obtained. The effects of different electric-magnetic boundary conditions on the phase velocity and mode shapes of displacements, electric and magnetic potentials have been discussed. The results show that the lowest mode is Rayleigh mode and that the phase velocities of the higher modes tend to the shear wave velocity of the piezoelectric layer as the frequency increases. The electric boundary conditions dominate the phase velocity. The magnetic boundary conditions have a significant effect on the mode shapes of the displacements, electric and magnetic potentials of the first mode. It is also found that piezoelectric material properties have an important effect on wave propagation. The result is relevant to the analysis and design of various acoustic surface wave devices constructed from piezoelectric and piezomagnetic materials.

A review of models for effective thermal conductivity of composite materials

Abstract: The solutions of Maxwell and Rayleigh were the first of many attempts to determine the eective thermal conductivity of heterogeneous material. Early models assumed that no thermal resistance exists between the phases in heterogeneous material. Later studies on solid-liquid and solid-solid boundaries revealed that a temperature drop occurs when heat flows through a boundary between two phases and, as a consequence, the interfacial thermal resistance should be included in the heat transfer model. This paper is a review of the most popular expressions for predicting the eective thermal conductivity of composite materials using the properties and volume fractions of constituent phases. Subject to review were empirical, analytical and numerical models, among others.

Universal Quantum Transducers based on Surface Acoustic Waves

Abstract: We propose a universal, on-chip quantum transducer based on surface acoustic waves in piezoactive materials. Because of the intrinsic piezoelectric (and/or magnetostrictive) properties of the material, our approach provides a universal platform capable of coherently linking a broad array of qubits, including quantum dots, trapped ions, nitrogen-vacancy centers, or superconducting qubits. The quantized modes of surface acoustic waves lie in the gigahertz range and can be strongly confined close to the surface in phononic cavities and guided in acoustic waveguides. We show that this type of surface acoustic excitation can be utilized efficiently as a quantum bus, serving as an on-chip, mechanical cavity-QED equivalent of microwave photons and enabling long-range coupling of a wide range of qubits.