相关论文: Crossover between hydrodynamic and kinetic modes i…
Inelastic X-ray scattering data have been collected for liquid sodium at T=390 K, i.e. slightly above the melting point. Owing to the very high instrumental resolution, pushed up to 1.5 meV, it has been possible to determine accurately the…
We observe pronounced oscillations in the differential reflectivity of a ferromagnetic InMnAs/GaSb heterostructure using two-color pump-probe spectroscopy. Although originally thought to be associated with the ferromagnetism, our studies…
A theory of the propagation of acoustic waves in a porous medium filled with superfluid solution is developed. The elastic coefficients in the system of equations are expressed in terms of physically measurable quantities. The equations…
To understand ultrasonic cavitation, it is imperative to analyze the effects of the gas-liquid phase transitions on soundwave propagation. Since current methods based on fluid dynamics offer limited information, it is imperative to carry…
The long-wavelength behavior of vibrational modes plays a central role in carrier transport, phonon-assisted optical properties, superconductivity, and thermomechanical and thermoelectric properties of materials. Here, we present general…
In amorphous solids, a non-negligible part of thermal conductivity results from phonon scattering on the structural disorder. The conversion of acoustic energy into thermal energy is often measured by the Dynamical Structure Factor (DSF)…
In high energy nuclear collisions, QCD jets deposit a large fraction of their energy into the produced matter. It has been proposed that as such matter behaves as a liquid with a very small viscosity, a fraction of this energy goes into a…
Owing to their large relatively thermal conductivity, peculiar, non-hydrodynamic features are expected to characterize the acoustic-like excitations observed in liquid metals. We report here an experimental study of collective modes in…
Two common concepts of nonreciprocity in sound propagation are based on nonlinear effects [1, 2] and on local circulation of fluid [3, 4]. They originate from two known methods of breaking a time reversal symmetry, that is necessary for…
We study the appearance of a sharp collective mode which features transverse current fluctuations within the bosonization approach to interacting two-dimensional Fermi liquids. This mode is analogous to the shear sound modes in elastic…
The high frequency dynamics of fluid oxygen have been investigated by Inelastic X-ray Scattering. In spite of the markedly supercritical conditions ($T\approx 2 T_c$, $P>10^2 P_c$), the sound velocity exceeds the hydrodynamic value of about…
We use metal nanostructures (nanoplasmonics) excited with dual frequency lasers to generate and detect high frequency (> 10 GHz) sound wave resonances in water. The difference frequency between the two lasers causes beating in the…
Motivated by the unusual soft mode anomalies in the relaxor ferroelectrics, we present a numerical study of vibrational excitations of a disordered lattice model with chemical order on the nano-scale. We find an Ioffe-Regel crossover in…
Two-dimensional stealthy hyperuniform distributions of rigid scatterers embedded in a waveguide are experimentally characterized the wave transport properties for scalar waves in airborne audible acoustics. The non resonant nature of the…
The attenuation rate of vibrational excitations in various metallic liquids and glasses has been reported to change from the quadratic dependence on wavevector at low wavevectors to the linear dependence at high wavevectors. However, the…
Scatterer induced modal coupling and the consequent mode splitting in a whispering gallery mode resonator is demonstrated in aqueous environment. The rate of change in splitting as particles enter the resonator mode volume strongly depends…
We investigate bright and dark solitons with anomalous or normal dispersion and under transverse harmonic confinement. In matter waves, positive atomic mass implies anomalous dispersion (kinetic spreading) while negative mass gives normal…
Transverse collective excitations in a binary liquid mixture are studied for different mass ratio of components $R$ at fixed numerical density. Increasing the mass ratio results in a larger gap width for shear waves. A four-variable dynamic…
We study the properties of the chromohydrodynamical instabilities induced by a relativistic jet that crosses the quark-gluon plasma. Assuming that the jet of particles and the plasma can be described using a hydrodynamical approach, we…
We review our theoretical results about the sound propagation in two-dimensional (2D) systems of ultracold fermionic and bosonic atoms. In the superfluid phase, characterized by the spontaneous symmetry breaking of the $U(1)$ symmetry,…