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arXiv · 1208.1659

Superfluid drag of two-species Bose-Einstein condensates in optical lattices

Patrick P. Hofer·C. Bruder·Vladimir M. Stojanovic
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Abstract

We study two-species Bose-Einstein condensates in quasi two-dimensional optical lattices of varying geometry and potential depth. Based on the numerically exact Bloch and Wannier functions obtained using the plane-wave expansion method, we quantify the drag (entrainment coupling) between the condensate components. This drag originates from the (short range) inter-species interaction and increases with the kinetic energy. As a result of the interplay between interaction and kinetic energy effects, the superfluid-drag coefficient shows a non-monotonic dependence on the lattice depth. To make contact with future experiments, we quantitatively investigate the drag for mass ratios corresponding to relevant atomic species.

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Patrick P. Hofer, C. Bruder, Vladimir M. Stojanovic. 2012-08-08. Superfluid drag of two-species Bose-Einstein condensates in optical lattices. https://doi.org/10.1103/physreva.86.033627

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