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Optically-induced lensing effect on a Bose-Einstein condensate expanding in a moving lattice

L. Fallani·F. S. Cataliotti·J. Catani·C. Fort·M. Modugno·M. Zawada·M. Inguscio
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Abstract

We report the experimental observation of a lensing effect on a Bose-Einstein condensate expanding in a moving 1D optical lattice. The effect of the periodic potential can be described by an effective mass dependent on the condensate quasi-momentum. By changing the velocity of the atoms in the frame of the optical lattice we induce a focusing of the condensate along the lattice direction. The experimental results are compared with the numerical predictions of an effective 1D theoretical model. Besides, a precise band spectroscopy of the system is carried out by looking at the real-space propagation of the atomic wavepacket in the optical lattice.

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L. Fallani, F. S. Cataliotti, J. Catani, C. Fort, M. Modugno, M. Zawada, M. Inguscio. 2004-01-21. Optically-induced lensing effect on a Bose-Einstein condensate expanding in a moving lattice. https://doi.org/10.1103/physrevlett.91.240405

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