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Cold Bose Gases near Feshbach Resonances

Yeong E. Kim·Alexander L. Zubarev
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Abstract

The lowest order constrained variational method [Phys. Rev. Lett. 88, 210403 (2002)] has been generalized for a dilute (in the sense that the range of interatomic potential is small compared with inter-particle spacing) uniform gas of bosons near the Feshbach resonance using the multi-channel zero-range potential model. The method has been applied to Na (F=1, m_F=1) atoms near the $B_0=907$G Feshbach resonance. It is shown that at high densities, there are significant differences between our results for the real part of energy per particle and the one-channel zero-range potential approximation. We point out the possibility of stabilization of the uniform con densate for the case of negative scattering length.

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Yeong E. Kim, Alexander L. Zubarev. 2003-05-29. Cold Bose Gases near Feshbach Resonances. https://arxiv.org/abs/cond-mat/0305692

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