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arXiv · 1107.1803

Precision Measurements on a Tunable Mott Insulator of Ultracold Atoms

M. J. Mark·E. Haller·K. Lauber·J. G. Danzl·A. J. Daley·H. -C. Nägerl
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Abstract

We perform precision measurements on a Mott-insulator quantum state of ultracold atoms with tunable interactions. We probe the dependence of the superfluid-to-Mott-insulator transition on the interaction strength and explore the limits of the standard Bose-Hubbard model description. By tuning the on-site interaction energies to values comparable to the interband separation, we are able to quantitatively measure number-dependent shifts in the excitation spectrum caused by effective multi-body interactions.

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M. J. Mark, E. Haller, K. Lauber, J. G. Danzl, A. J. Daley, H. -C. Nägerl. 2011-07-09. Precision Measurements on a Tunable Mott Insulator of Ultracold Atoms. https://doi.org/10.1103/physrevlett.107.175301

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