Dynamics of trapped Bose gases at finite temperatures
| dc.creator | Zaremba, E. | |
| dc.creator | Nikuni, T. | |
| dc.creator | Griffin, A. | |
| dc.date | 1999-03-02 | |
| dc.date | 1999-06-15 | |
| dc.date.accessioned | 2026-07-07T03:12:55Z | |
| dc.date.available | 2026-07-07T03:12:55Z | |
| dc.description | Starting from an approximate microscopic model of a trapped Bose-condensed gas at finite temperatures, we derive an equation of motion for the condensate wavefunction and a quantum kinetic equation for the distribution function for the excited atoms. The kinetic equation includes collisions between the condensate and non-condensate atoms ($C_{12}$), in addition to collisions between the excited atoms as described by the Uehling-Uhlenbeck ($C_{22}$) collision integral. Assuming that the $C_{22}$ collision rate is sufficiently rapid to produce a local equilibrium Bose distribution, the kinetic equation can be used to derive hydrodynamic equations for the non-condensate. These equations include a description of the equilibration of the local chemical potentials of the condensate and non-condensate components which gives rise to a new relaxational mode associated with the exchange of atoms between the two components. We show how the Landau two-fluid equations emerge in the frequency domain $ωτ_μ\ll 1$, where $τ_μ$ is a characteristic relaxation time of the equilibration process. This process provides an additional source of damping of the collective modes (first and second sound in the case of a uniform system). Our equations are consistent with the generalized Kohn theorem. Finally, a variational solution of the equations is developed which is used to determine some of the monopole, dipole and quadrupole normal modes of a trapped Bose gas in an isotropic trap. | |
| dc.description | 54 pages, revtex, 6 postscript figures, final version accepted for publication in Journ. Low Temp. Physics | |
| dc.identifier | https://arxiv.org/abs/cond-mat/9903029 | |
| dc.identifier | http://arxiv.org/abs/cond-mat/9903029 | |
| dc.identifier.uri | http://salesiana.dossiersoluciones.com/handle/123456789/29095 | |
| dc.subject | Statistical Mechanics | |
| dc.title | Dynamics of trapped Bose gases at finite temperatures | |
| dc.type | text |