In this paper we study the existence and uniqueness of interfacial waves in account of surface elasticity at the interface. A sufficient condition for the existence and uniqueness of a subsonic interfacial wave between two elastic half-spaces is obtained for general anisotropic materials. Further, we explicitly calculate the dispersion relations of interfacial waves for interfaces between two s...

Observations show the increase of high-frequency wave power near magnetic network cores and active regions in the solar lower atmosphere. This phenomenon can be explained by the interaction of acoustic waves with a magnetic field. We consider small-scale, bipolar, magnetic field canopy structure near the network cores and active regions overlying field-free cylindrical cavities of the photosphe...

We examine the influence of a random flow that occurs in the convection zone on frequencies of the solar acoustic oscillations. Using a perturbative method the dispersion relation is derived in the case of a random flow that is parallel to the wave propagation. This relation is subsequently solved numerically for various parameters of the random field to find the frequencies of the random acous...

A method has been developed to measure the phase velocity of laser generated and detected surface acoustic waves. An optical grating produced by an electronically addressable spatial light modulator (SLM) was imaged onto the sample surface to generate surface acoustic waves whose frequency and wavefront was controlled by the SLM. When the grating period matched the surface acoustic wavelength, ...

Full waveform inversion (FWI) has been used to successfully build high-resolution earth velocity models for marine data. For land data sets, FWI using acoustic wave equation (acoustic-FWI) remains challenging due to the lack of modeling of strong surface waves, converted waves, phase dispersion, and near-surface weathering layer distortion. In addition, for land dynamite surveys, the source wav...

In this work, a model is proposed to predict acoustic waves generated in a homogeneous and isotropic cylindrical cavity by a laser line source. The Fourier series expansion is introduced for one spatial coordinate to solve this transient response problem. Theoretical displacements are obtained for an aluminum cylindrical cavity of internal diameter 40 mm. The corresponding displacements are obs...

Coherent folded longitudinal acoustic phonons in a GaAs/AlAs long-period superlattice have been investigated by using a reflection-type two-color pump-probe technique under the condition that the wave vector of the probe pulse in the sample exceeds the mini-Brillouin zone. The coherent oscillations observed in the time-domain signals indicate the propagation of the phonon wave packet through th...

We demonstrate the confinement of acoustic phonons in ultrathin silicon layers and study its effect on electron mobility. We develop a model for confined acoustic phonons in an ideal single-layer structure and in a more realistic three-layer structure. Phonon quantization is recovered, and the dispersion relations for distinct phonon modes are computed. This allows us to obtain the confined pho...

Similar to electron waves, the phonon states in semiconductors can undergo changes induced by external boundaries. However, despite strong scientific and practical importance, conclusive experimental evidence of confined acoustic phonon polarization branches in individual free-standing nanostructures is lacking. Here we report results of Brillouin-Mandelstam light scattering spectroscopy, which...

We apply the CIP (Cubic Interpolated Profile) scheme to the numerical simulation of the acoustic wave propagation based on characteristic equations.The CIP scheme is based on a concept that both the wavefield and its spatial derivative propagate along the same characteristic curves derived from a hyperbolic differential equation. We describe the derivation of the characteristic equations for th...