| Modern atom-optics experiments allow one an unprecedented control of atomic degrees of freedom and, as a consequence, the clean realization of toy models used to explain transport phenomena in condensed matter physics. We present recent results on extended Bose-Hubbard systems. For reasonable lattice sizes, this model gives access to the full quantum spectrum, which allows us a complete characterization of "horizontal" (spatially) and "vertical" (energetic) quantum transport. Various dynamical regimes can be prepared, using atom-atom interactions, disorder, and external forces as control parameters. We show that the inter-band transport of atoms - confined to a periodic lattice and subject to an additional tilting force - is strongly dependent on the dynamics of the ground-state band. Analogies between Stark localisation and Anderson localisation are discussed, as well as predictions for experiments to observe signatures of complex inter-band dynamics with ultracold atoms. |
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