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arXiv · 1209.4046

Disordered Bose Einstein Condensates with Interaction

Robert Seiringer·Jakob Yngvason·Valentin A. Zagrebnov
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Abstract

We study the effects of random scatterers on the ground state of the one-dimensional Lieb-Liniger model of interacting bosons on the unit interval in the Gross-Pitaevskii regime. We prove that Bose Einstein condensation survives even a strong random potential with a high density of scatterers. The character of the wave function of the condensate, however, depends in an essential way on the interplay between randomness and the strength of the two-body interaction. For low density of scatterers or strong interactions the wave function extends over the whole interval. High density of scatterers and weak interaction, on the other hand, leads to localization of the wave function in a fragmented subset of the interval.

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Robert Seiringer, Jakob Yngvason, Valentin A. Zagrebnov. 2012-09-18. Disordered Bose Einstein Condensates with Interaction. https://arxiv.org/abs/1209.4046

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