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arXiv · 1006.5312

Dynamics of pair correlations in the attractive Lieb-Liniger gas

Dominik Muth·Michael Fleischhauer
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Abstract

We investigate the dynamics of a 1D Bose gas after a quench from the Tonks-Girardeau regime to the regime of strong attractive interactions applying analytical techniques and exact numerical simulations. After the quench the system is found to be predominantly in an excited gas-like state, the so-called super-Tonks gas, however with a small coherent admixture of two-particle bound states. Despite its small amplitude, the latter component leads to a rather pronounced oscillation of the local density-density correlation with a frequency corresponding to the binding energy of the pair, making two-particle bound states observable in an experiment. Contributions from bound states with larger particle numbers are found to be negligible.

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Dominik Muth, Michael Fleischhauer. 2010-06-28. Dynamics of pair correlations in the attractive Lieb-Liniger gas. https://doi.org/10.1103/physrevlett.105.150403

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