Localized states and interaction-induced delocalization in Bose gases with quenched disorderG. M. Falco1, T. Nattermann1 and V. L. Pokrovsky2, 3
1 Institut für Theoretische Physik, Universität zu Köln - Zülpicher Str. 77, D-50937 Köln, Germany, EU
2 Department of Physics, Texas A&M University - College Station, TX 77843-4242, USA
3 Landau Institute for Theoretical Physics - Chernogolovka, Moscow District 142432, Russia
received on 17 November 2008; accepted in final form by M. Lewenstein on 13 January 2009; published February 2009
published online 29 January 2009
Very diluted Bose gas placed into a disordered environment falls into a fragmented localized state. At some critical density the repulsion between particles overcomes the disorder. The gas transits into a coherent superfluid state. In this article the geometrical and energetic characteristics of the localized state at zero temperature and the critical density at which the quantum phase transition from the localized to the superfluid state proceeds are found.
03.75.Hh - Static properties of condensates; thermodynamical, statistical, and structural properties.
03.75.Kk - Dynamic properties of condensates; collective and hydrodynamic excitations, superfluid flow.
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