Condensate localization in a quasi-periodic structure

Y. Eksioglu; P. Vignolo; M. P. Tosi

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Condensate localization in a quasi-periodic structure

Y. Eksioglu·P. Vignolo·M. P. Tosi

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Abstract

We propose a set-up of optical laser beams by which one may realize a quasi-one-dimensional Fibonacci array of potential wells for a Bose-Einstein condensate. We use a Bose-Hubbard tight-binding model to evaluate the transport of superfluid Rb87 atoms driven by a constant force through such an array. We show that the minigaps that are generated in the spectral density-of-states by the quasi-periodic disorder give rise to prominent localization effects, which can be observed by measuring the tunnel output of matter into vacuum as a function of the intensity of the applied force.

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Y. Eksioglu, P. Vignolo, M. P. Tosi. 2004-05-19. Condensate localization in a quasi-periodic structure. https://arxiv.org/abs/cond-mat/0405440

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