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A toy model for molecular condensates in Bose gases

L. Pricoupenko
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Abstract

The occurrence of a molecular Bose-Einstein condensate is studied for an atomic system near a zero energy resonance of the binary scattering process, with a large and positive scattering length. The interaction potential is modeled by a pseudo-potential having one bound state. Using a variational Gaussian ansatz for the $N$-body density operator, we discuss the thermodynamic properties at low temperature and the relative stability of the system towards the formation of an atomic Bose-Einstein condensate. We also derive an approximate Gross-Pitaevskii equation for the molecular condensate leading to the prediction of a Bogoliubov spectrum.

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L. Pricoupenko. 2000-06-16. A toy model for molecular condensates in Bose gases. https://arxiv.org/abs/cond-mat/0006263

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