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Bloch oscillations and mean-field effects of Bose-Einstein condensates in 1-D optical lattices

O. Morsch·J. H. Müller·M. Cristiani·D. Ciampini·E. Arimondo
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Abstract

We have loaded Bose-Einstein condensates into one-dimensional, off-resonant optical lattices and accelerated them by chirping the frequency difference between the two lattice beams. For small values of the lattice well-depth, Bloch oscillations were observed. Reducing the potential depth further, Landau-Zener tunneling out of the lowest lattice band, leading to a breakdown of the oscillations, was also studied and used as a probe for the effective potential resulting from mean-field interactions as predicted by Choi and Niu [Phys. Rev. Lett. {\bf 82}, 2022 (1999)]. The effective potential was measured for various condensate densities and trap geometries, yielding good qualitative agreement with theoretical calculations.

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O. Morsch, J. H. Müller, M. Cristiani, D. Ciampini, E. Arimondo. 2001-08-28. Bloch oscillations and mean-field effects of Bose-Einstein condensates in 1-D optical lattices. https://doi.org/10.1103/physrevlett.87.140402

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