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arXiv · 2203.09922

Bose-Einstein condensate in an elliptical waveguide

L. Salasnich
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Abstract

We investigate the effects of spatial curvature for an atomic Bose-Einstein condensate confined in an elliptical waveguide. The system is well described by an effective 1D Gross-Pitaevskii equation with a quantum-curvature potential, which has the shape of a double-well but crucially depends on the eccentricity of the ellipse. The ground state of the system displays a quantum phase transition from a two-peak configuration to a one-peak configuration at a critical attractive interaction strength. In correspondence of this phase transition the superfluid fraction strongly reduces and goes to zero for a sufficiently attractive Bose-Bose interaction.

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L. Salasnich. 2022-03-18. Bose-Einstein condensate in an elliptical waveguide. https://doi.org/10.21468/scipostphyscore.5.1.015

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