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Topology Induced Spatial Bose-Einstein Condensation for Bosons on Star-Shaped Optical Networks

I. Brunelli·G. Giusiano·F. P. Mancini·P. Sodano·A. Trombettoni
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Abstract

New coherent states may be induced by pertinently engineering the topology of a network. As an example, we consider the properties of non-interacting bosons on a star network, which may be realized with a dilute atomic gas in a star-shaped deep optical lattice. The ground state is localized around the star center and it is macroscopically occupied below the Bose-Einstein condensation temperature T_c. We show that T_c depends only on the number of the star arms and on the Josephson energy of the bosonic Josephson junctions and that the non-condensate fraction is simply given by the reduced temperature T/T_c.

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I. Brunelli, G. Giusiano, F. P. Mancini, P. Sodano, A. Trombettoni. 2004-04-21. Topology Induced Spatial Bose-Einstein Condensation for Bosons on Star-Shaped Optical Networks. https://doi.org/10.1088/0953-4075%2F37%2F7%2F072

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