Physics – Condensed Matter – Statistical Mechanics
Scientific paper
2000-09-21
Physics
Condensed Matter
Statistical Mechanics
26 pages, 3 postscript figures, submitted to PRA
Scientific paper
10.1103/PhysRevA.63.033608
Starting from the quantum kinetic equation for the non-condensate atoms and the generalized Gross-Pitaevskii equation for the condensate, we derive the two-fluid hydrodynamic equations of a trapped Bose gas at finite temperatures. We follow the standard Chapman-Enskog procedure, starting from a solution of the kinetic equation corresponding to the complete local equilibrium between the condensate and the non-condensate components. Our hydrodynamic equations are shown to reduce to a form identical to the well-known Landau-Khalatnikov two-fluid equations, with hydrodynamic damping due to the deviation from local equilibrium. The deviation from local equilibrium within the thermal cloud gives rise to dissipation associated with shear viscosity and thermal conduction. In addition, we show that effects due to the deviation from the diffusive local equilibrium between the condensate and the non-condensate (recently considered by Zaremba, Nikuni and Griffin) can be described by four frequency-dependent second viscosity transport coefficients. We also derive explicit formulas for all the transport coefficients. These results are used to introduce two new characteristic relaxation times associated with hydrodynamic damping. These relaxation times give the rate at which local equilibrium is reached and hence determine whether one is in the two-fluid hydrodynamic region.
Griffin Allan
Nikuni Tetsuro
No associations
LandOfFree
Landau-Khalatnikov two-fluid hydrodynamics of a trapped Bose gas does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Landau-Khalatnikov two-fluid hydrodynamics of a trapped Bose gas, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Landau-Khalatnikov two-fluid hydrodynamics of a trapped Bose gas will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-131313