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arXiv · 0707.0981

Boson Pairs in a One-dimensional Split Trap

D. S. Murphy·J. F. McCann·J. Goold·Th. Busch
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Abstract

We describe the properties of a pair of ultracold bosonic atoms in a one-dimensional harmonic trapping potential with a tunable zero-ranged barrier at the trap centre. The full characterisation of the ground state is done by calculating the reduced single-particle density, the momentum distribution and the two-particle entanglement. We derive several analytical expressions in the limit of infinite repulsion (Tonks-Girardeau limit) and extend the treatment to finite interparticle interactions by numerical solution. As pair interactions in double wells form a fundamental building block for many-body systems in periodic potentials, our results have implications for a wide range of problems.

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D. S. Murphy, J. F. McCann, J. Goold, Th. Busch. 2007-07-06. Boson Pairs in a One-dimensional Split Trap. https://doi.org/10.1103/physreva.76.053616

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