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Adiabatically changing the phase-space density of a trapped Bose gas

P. W. H. Pinkse·A. Mosk·M. Weidemüller·M. W. Reynolds·T. W. Hijmans·J. T. M. Walraven
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Abstract

We show that the degeneracy parameter of a trapped Bose gas can be changed adiabatically in a reversible way, both in the Boltzmann regime and in the degenerate Bose regime. We have performed measurements on spin-polarized atomic hydrogen in the Boltzmann regime demonstrating reversible changes of the degeneracy parameter (phase-space density) by more than a factor of two. This result is in perfect agreement with theory. By extending our theoretical analysis to the quantum degenerate regime we predict that, starting close enough to the Bose-Einstein phase transition, one can cross the transition by an adiabatic change of the trap shape.

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P. W. H. Pinkse, A. Mosk, M. Weidemüller, M. W. Reynolds, T. W. Hijmans, J. T. M. Walraven. 1996-11-27. Adiabatically changing the phase-space density of a trapped Bose gas. https://doi.org/10.1103/physrevlett.78.990

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