Love-wave-based MEMS devices are theoretically investigated in their potential role as a promising technological platform for the development of acoustic-wave-based sensors for liquid environments. Both single- and bi-layered structures have been investigated and the velocity dispersion curves were calculated for different layer thicknesses, crystallographic orientations, material types and electrical boundary conditions. High velocity materials have been investigated too, enabling device miniaturization, power consumption reduction and integration with the conditioning electronic circuits. The electroacoustic coupling coefficient dispersion curves of the first four Love modes are calculated for four dispersive coupling configurations based on a c-axis tilted ZnO layer on wz-BN substrate. The gravimetric sensitivity of four Love modes travelling at a common velocity of 9318 m/s along different layer thicknesses, and of three Love modes travelling at different velocity along a fixed ZnO layer thickness, are calculated in order to design enhanced-performance sensors. The phase velocity shift and attenuation due to the presence of a viscous liquid contacting the device surface are calculated for different thicknesses of a c-axis inclined ZnO layer onto BN half-space.

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A theoretical formalism for calculating the bulk and surface spin modes in Heisenberg semi-infinite lattices is presented on a ferromagnetic cubic network of spins, coupled via nearest and next-nearest neighbors exchange interactions. The magnetic surface can be considered as semi-infinite slabs at the end of the bulk structures. The breakdown of translation symmetry, in the normal direction of the surface, gives rise to localized spin wave modes in its neighborhood. The localized magnon spectrum is derived as elements of a Landauer-type scattering matrix, in the three cubic lattices sc, bcc and fcc. The magnon properties are simulated and determined numerically for each cubic lattice by using the matching technique. The observed fluctuations in the numerical results demonstrate the interference magnon effects between scattered spinwaves and the localized magnon states, generated by the surface region with characteristic Fano resonances. In cubic leads, the localized surface spin states are sensitive to the local magnetic coupling and the incident direction in the surface boundary. In this contribution, the normalized energy of spinwaves arising from the absence of translation symmetry is analyzed for each cubic system as a function of the exchange integral parameters. This addresses the dependence of the surface magnon on the different possibilities of the of the exchange parameters variation from softening to hardening in the neighborhood of the surface region.