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arXiv · 1109.2971

Effective Field Theory for Atom-Molecule Systems II: Stationary Solutions and Bogoliubov Excitations in Atom-Molecule Systems

Catarina E Sahlberg·C W Gardiner
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Abstract

We formulate the basic theoretical methods for Bose-Einstein Condensation of atoms close to a Feshbach resonance, in which the tunable scattering length of the atoms is described using a system of coupled atom and molecule fields. These include the Thomas-Fermi description of the condensate profile, the c-field equations, and the Bogoliubov-de Gennes equations, and the Bogoliubov excitation spectrum for a homogenous condensed system. We apply this formalism to the special case of Bragg scattering from a uniform condensate, and find that for moderate and large scattering lengths, there is a dramatic difference in the shift of the peak of the Bragg spectra, compared to that based on a structureless atom model. The result is compatible with the experimental results of Papp et al. [S. B. Papp et al., Phys. Rev. Lett., 101(13):135301, Sep 2008].

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Catarina E Sahlberg, C W Gardiner. 2011-09-14. Effective Field Theory for Atom-Molecule Systems II: Stationary Solutions and Bogoliubov Excitations in Atom-Molecule Systems. https://arxiv.org/abs/1109.2971

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