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arXiv:cond-mat/0307402 · Physical Review Letters

Disordered Bose-Einstein Condensates in Quasi-One-Dimensional Magnetic Microtraps

Daw-Wei Wang, Mikhail D. Lukin, Eugene Demler

Published Feb 18, 2004• 107 citations
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Abstract

We analyze the effects of a random magnetic potential in a microfabricated waveguide for ultracold atoms. We find that the shape and position fluctuations of a current carrying wire induce a strong Gaussian correlated random potential with a length scale set by the atom-wire separation. The theory is used to explain quantitatively the observed fragmentation of the Bose-Einstein condensates in atomic waveguides. Furthermore, we show that nonlinear dynamics can be used to provide important insights into the nature of the strongly fragmented condensates. We argue that a quantum phase transition from the superfluid to the insulating Bose glass phase may be reached and detected under the realistic experimental conditions.

DOI
10.1103/physrevlett.92.076802

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