Related papers: The two-fluid model with superfluid entropy
In recent years, experimental data were published which point to the possibility of the existence of superfluidity in solid helium. To investigate this phenomenon theoretically we employ a hierarchy of equations for reduced density matrices…
In this paper we show that a recent hydrodynamical model of superfluid turbulence describes vortex density waves and their effects on the speed of high-frequency second sound. In this frequency regime, the vortex dynamics is not purely…
We study a holographic model of a relativistic quantum system with a global U(1) symmetry, at non-zero temperature and density. When the temperature falls below a critical value, we find a second-order superfluid phase transition with…
The phenomenon of superconductivity was explained as a consequence of ordering of zero-point oscillations. Superfluidity are related phenomenon. The consideration of interaction zero-point oscillations in liquid helium permit to obtain…
This article presents a phenomenological dynamic phase transition theory -- modeling and analysis -- for liquid helium-3. We derived two new models, for liquid helium-3 with or without applied field, by introducing three wave functions and…
We have recently derived two-fluid hydrodynamic equations for a trapped weakly-interacting Bose gas. In this paper, we use these equations to discuss first and second sound in a uniform Bose gas. These results are shown to agree with the…
Second sound is an entropy wave which propagates in the superfluid component of a quantum liquid. Because it is an entropy wave, it probes the thermodynamic properties of the quantum liquid which are determined, e.g., by the interaction…
A propagation torsion model for quantized vortices is proposed.The model is applied to superfluids and liquid Helium II.
We consider reflection of the first and the second sound waves by a rigid flat wall in superfluid. Nontrivial dependence of the reflection coefficients on the angle of incidence is obtained. Sound conversion is predicted at slanted…
The first successful macroscopic theory for the motion of superfluid helium was that of Lev Landau (1941) in which the fluid is modelled phenomenologically as an interpenetrating mixture of a superfluid and a normal fluid. It has later been…
Based upon the hypothesis of simultaneous participation of helium particles in atom(atom) and pair(pair) motions, the proof of Feynman and Bogoliubov formulas validity for elementary excitations spectrum in superfluid helium is carried out…
Superfluidity in Fermi systems is not destroyed by a flow exceeding the Landau velocity threshold. The overcritical state acquires normal component even at zero temperature. We explore peculiar hydrodynamics of this system and discover two…
New models of Turbulence, Superfluidity and Superconductivity, based on new Hierarchic theory, general for liquids and solids (physics/0102086), have been proposed. CONTENTS: 1 Turbulence. General description; 2 Mesoscopic mechanism of…
The normal density of a translation-invariant superfluid often vanishes at zero temperature, as is observed in superfluid Helium and conventional superconductors described by BCS theory. Here we show that this need not be the case. We…
Sound propagation is a macroscopic manifestation of the interplay between the equilibrium thermodynamics and the dynamical transport properties of fluids. Here, for a two-dimensional system of ultracold fermions, we calculate the first and…
Acoustic metafluids are defined as the class of fluids that allow one domain of fluid to acoustically mimic another, as exemplified by acoustic cloaks. It is shown that the most general class of acoustic metafluids are materials with…
Guided by the analogy to the Bose-Einstein condensation of the ideal Bose gas (IBG) we propose a new model for the lambda transition of liquid helium. Deviating from the IBG our model uses phase ordered and localized single-particle…
We point out that two different definitions of the superfluid density - through statistical response to static gauge phase and through dynamic response to altering gauge phase - yield, generally speaking, different quantities in $d<3$. The…
A theory accounting for the dynamical aspects of the superfluid response of one dimensional (1D) quantum fluids is reported. In long 1D systems the onset of superfluidity is related to the dynamical suppression of quantum phase slips at low…
We discuss and review the basic physics that leads to superfluidity/superconductivity in certain quantum Hall states, in particular the so-called double-layered (mmm) state. In the K-matrix description of the quantum correlation in quantum…