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Classical chaos with Bose-Einstein condensates in tilted optical lattices

Quentin Thommen·Jean Claude Garreau·Véronique Zehnlé
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Abstract

A widely accepted definition of ``quantum chaos'' is ``the behavior of a quantum system whose \emph{classical} \emph{limit is chaotic}''. The dynamics of quantum-chaotic systems is nevertheless very different from that of their classical counterparts. A fundamental reason for that is the linearity of Schr{ö}dinger equation. In this paper, we study the quantum dynamics of an ultra-cold quantum degenerate gas in a tilted optical lattice and show that it displays features very close to \emph{classical} chaos. We show that its phase space is organized according to the Kolmogorov-Arnold-Moser theorem.

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Quentin Thommen, Jean Claude Garreau, Véronique Zehnlé. 2003-06-25. Classical chaos with Bose-Einstein condensates in tilted optical lattices. https://doi.org/10.1103/physrevlett.91.210405

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