arXiv 0806.48952008-06-30cond-mat.othercond-mat.stat-mech

Collective Excitations of Harmonically Trapped Ideal Gases

Bert Van Schaeybroeck, Achilleas Lazarides

备注：: 4 pages, submitted to special issue of Eur. Phys. J. B "Novel Quantum Phases and Mesoscopic Physics in Quantum Gases"
发表信息：: Eur. Phys. J. B 68, 329 (2009)
DOI：: 10.1140/epjb/e2008-00420-6

英文摘要：

We theoretically study the collective excitations of an ideal gas confined in an isotropic harmonic trap. We give an exact solution to the Boltzmann-Vlasov equation; as expected for a single-component system, the associated mode frequencies are integer multiples of the trapping frequency. We show that the expressions found by the scaling ansatz method are a special case of our solution. Our findings, however, are most useful in case the trap contains more than one phase: we demonstrate how to obtain the oscillation frequencies in case an interface is present between the ideal gas and a different phase.

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