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

Daw-Wei Wang·Mikhail D. Lukin·Eugene Demler
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Abstract

We analyze effects of a random magnetic potential in a microfabricated waveguide for ultra-cold atoms. We find that the shape and position fluctuations of a current carrying wire induce strongly disordered potential that is quasiperiodic with a lengthscale set by the atom-wire separation. The theory is used to explain quantitatively the experimentally observed fragmentation of the quasi one-dimensional Bose-Einstein condensates. 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.

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Daw-Wei Wang, Mikhail D. Lukin, Eugene Demler. 2004-03-01. Disordered Bose-Einstein Condensates in Quasi One-Dimensional Magnetic Microtraps. https://doi.org/10.1103/physrevlett.92.076802

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