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arXiv · 0807.4504

Role of interactions in 87Rb-40K Bose-Fermi mixtures in a 3d optical lattice

Th. Best·S. Will·U. Schneider·L. Hackermueller·D. -S. Luehmann·D. van Oosten·I. Bloch
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Abstract

We investigate the effect of interspecies interaction on a degenerate mixture of bosonic 87Rb and fermionic 40K atoms in a three-dimensional optical lattice potential. Using a Feshbach resonance, the 87Rb-40K interaction is tuned over a wide range. Through an analysis of the 87Rb momentum distribution, we find a pronounced asymmetry between strong repulsion and strong attraction. In the latter case, the Bose-Hubbard parameters are renormalized due to self-trapping, leading to a marked shift in the superfluid to Mott insulator transition with increasing Bose-Fermi interaction.

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Th. Best, S. Will, U. Schneider, L. Hackermueller, D. -S. Luehmann, D. van Oosten, I. Bloch. 2008-07-28. Role of interactions in 87Rb-40K Bose-Fermi mixtures in a 3d optical lattice. https://doi.org/10.1103/physrevlett.102.030408

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