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Collapses and Revivals of Collective Excitations in Trapped Bose Condensates

R. Graham·D. F. Walls·M. J. Collett·M. Fliesser·E. M. Wright
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Abstract

We present a quantum theory of low-lying excitations in a trapped Bose condensate with finite particle numbers. We find that even at zero temperature condensate number fluctuations and/or fluctuations of the excitation frequency due to quantum uncertainties of the mode occupation lead to a collapse of the collective modes due to dephasing. Coherent revivals of the collective excitations are predicted on a much longer timescale. Depletion of collective modes due to second-harmonic generation is discussed.

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R. Graham, D. F. Walls, M. J. Collett, M. Fliesser, E. M. Wright. 1997-09-05. Collapses and Revivals of Collective Excitations in Trapped Bose Condensates. https://arxiv.org/abs/cond-mat/9612060

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