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Quasi-one-dimensional Bose gases with large scattering length

G. E. Astrakharchik·D. Blume·S. Giorgini·B. E. Granger
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Abstract

Bose gases confined in highly-elongated harmonic traps are investigated over a wide range of interaction strengths using quantum Monte Carlo techniques. We find that the properties of a Bose gas under tight transverse confinement are well reproduced by a 1d model Hamiltonian with contact interactions. We point out the existence of a unitary regime, where the properties of the quasi-1d Bose gas become independent of the actual value of the 3d scattering length. In this unitary regime, the energy of the system is well described by a hard rod equation of state. We investigate the stability of quasi-1d Bose gases with positive and negative 3d scattering length.

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G. E. Astrakharchik, D. Blume, S. Giorgini, B. E. Granger. 2003-08-27. Quasi-one-dimensional Bose gases with large scattering length. https://doi.org/10.1103/physrevlett.92.030402

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