相关论文: First sound velocity in liquid $^{4}$He
Hydrodynamic heat flow, where out-of-equilibrium phonons collectively drift in response to an applied temperature differential, has attracted renewed interest following its experimental observation in graphite at temperatures as high as 300…
We investigate the speed of sound in nuclear matter at finite temperature and density~(chemical potential) in the nonlinear Walecka model. The numerical results suggest that the behaviors of sound speed are closely related to the the…
This work aims to address the technical aspects related to the thermodynamic characterization of natural gas mixtures blended with hydrogen for the introduction of alternative energy sources within the Power-to-Gas framework. For that…
In the present work we determine the speed of sound in a Bose-Einstein condensate confined by an isotropic harmonic oscillator trap. The deduction of this physical parameter is done resorting to the $N$-body Hamiltonian operator. The…
We measured high-speed sound propagation in a near-critical fluid using a ultra-sensitive interferometer to investigate adiabatic changes of fluids on acoustic timescales. A sound emitted by very weak continuous heating caused a stepwise…
Superfluid $^3$He confined in aerogel offers a unique chance to study the effects of a short mean free path on the properties of a well defined superfluid Fermi liquid with anisotropic pairing. Transport coefficients and collective…
In order to understand the detailed dynamics of systems produced in $pp$ collisions, it is essential to know about the Equation of State (EoS) and various thermodynamic properties. In this work, we study the shear viscosity to entropy…
We consider a non-relativistic quantum gas of $N$ bosonic atoms confined to a box of volume $\Lambda$ in physical space. The atoms interact with each other through a pair potential whose strength is inversely proportional to the density,…
We study the response of one-dimensional liquid $^4$He to weak perturbations relying on the dynamical structure factor, $S(q,\omega)$, recently obtained via ab-initio techniques [Phys. Rev. Lett. 116, 135302 (2016)]. We evaluate the drag…
The sound velocity in selected liquid alloys of the isomorphous Bi-Sb system was measured as a function of temperature to a high accuracy of 0.2%. The sound velocity temperature coefficient, dlnc/dT, at the liquidus is found to vary…
We present results of the search for supersolid 4He using low-frequency, low-level mechanical excitation of a solid sample grown and cooled at fixed volume. We have observed low frequency non-linear resonances that constitute anomalous…
A normal-fluid component varying as T$^{2}$ is observed at very low temperatures in superfluid $^4$He and $^3$He-$^4$He mixture films adsorbed in alumina powder. The normal fluid appears to arise from thermally excited third sound that has…
Thermodynamic properties of hot and dense hadronic systems with a hard-sphere interaction are calculated in the Boltzmann approximation. Two parametrizations of pressure as a function of density are considered: the first one, used in the…
The generation of hydrodynamic radiation in interactions of pulsed proton and laser beams with matter is explored. The beams were directed into a water target and the resulting acoustic signals were recorded with pressure sensitive sensors.…
Fundamental considerations predict that macroscopic quantum systems such as superfluids and the electrons in superconductors will exhibit oscillatory motion when pushed through a small constriction. Here we report the observation of these…
A simple and popular Bridgman's formula predicts a linear correlation between the thermal conductivity coefficient and the sound velocity of dense liquids. Unfortunately, it cannot be applied to strongly coupled plasma-related fluids,…
Superfluid $^4$He at a finite temperature is described by the two-fluid model with the normal fluid component and the superfluid component.We formulate the two-fluid model for two-component BECs, namely two-superfluid model, starting from…
We investigated the structural and dynamical properties of a tetrahedrally coordinated crystalline ice from first principles based on density functional theory within the generalized gradient approximation with the projected augmented wave…
Sound waves in bubbly water and light in special relativity obey identical first-order transport laws. This equivalence is not approximate or analogical but mathematically identical to first order in $U/v$, sharing the same form discovered…
We compare recent experimental results [Science 375, 528 (2022)] of the superfluid unitary Fermi gas near the critical temperature with a thermodynamic model based on elementary excitations of the system. We find very good agreement between…