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arXiv · 1012.1360

How localized bosons manage to become superfluid

Luca Dell'Anna·Michele Fabrizio
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Abstract

We study the superfluid-to-Bose glass transition in a disordered Bose-Hubbard model through a very simple variational wavefunction: a permanent of non-orthogonal single-particle wavefunctions that are variationally determined. The transition is identified by the behavior of the superfluid stiffness. We also introduce a less rigorous but very enlightening criterium for the transition, which is related to the overlap matrix among the single-particle wavefunctions that are used to built the permanent. We find that the two criteria agree quite well. We finally consider a further quantity, the bipartite entanglement entropy, which also provides a good estimator for the superfluid-to-Bose glass transition.

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Luca Dell'Anna, Michele Fabrizio. 2011-07-15. How localized bosons manage to become superfluid. https://doi.org/10.1088/1742-5468%2F2011%2F08%2Fp08004

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