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The Roton in a Bose-Einstein Condensate

J. Steinhauer·R. Ozeri·N. Katz·N. Davidson
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Abstract

The roton in a Bose-Einstein condensate is computed, both near and far from a Feshbach resonance. A low-density approximation is made, allowing for an analytic result. A Monte Carlo calculation shows that the roton is larger than predicted by the low-density approximation, for the upper range of densities considered here. The low-density approximation is applied to superfluid 4He, roughly reproducing the results of previous Monte Carlo calculations.

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J. Steinhauer, R. Ozeri, N. Katz, N. Davidson. 2004-01-27. The Roton in a Bose-Einstein Condensate. https://arxiv.org/abs/cond-mat/0303375

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