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arXiv · 2004.00936

Interacting Bose gas across a narrow Feshbach resonance

Fan Yang·Ran Qi
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Abstract

We use a two-channel model to investigate an interacting Bose gas across a narrow Feshbach resonance within a field path integral approach. The ground state properties show strong deviation from that of a broad Feshbach resonance or a single channel interaction. The deviation can be interpreted by the strong energy dependence of two-body scattering length near a narrow Feshbach resonance. As the density increases, the chemical potential and energy per particle are found to saturate while the inverse compressibility and phonon velocity undergo a significant reduction. We also take Gaussian fluctuations into account and calculate the ground state energy correction as well as the quantum depletion.

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Fan Yang, Ran Qi. 2020-04-02. Interacting Bose gas across a narrow Feshbach resonance. https://arxiv.org/abs/2004.00936

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