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arXiv · 1202.2653

Anomalous spatial diffusion and multifractality in optical lattices

A. Dechant·E. Lutz
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Abstract

Transport of cold atoms in shallow optical lattices is characterized by slow, nonstationary momentum relaxation. We here develop a projector operator method able to derive in this case a generalized Smoluchowski equation for the position variable. We show that this explicitly non-Markovian equation can be written as a systematic expansion involving higher-order derivatives. We use the latter to compute arbitrary moments of the spatial distribution and analyze their multifractal properties.

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BibTeXRIS

A. Dechant, E. Lutz. 2012-02-13. Anomalous spatial diffusion and multifractality in optical lattices. https://doi.org/10.1103/physrevlett.108.230601

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