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arXiv · 0707.1980

Atomic Landau-Zener tunneling in Fourier-synthesized optical lattices

Tobias Salger·Carsten Geckeler·Sebastian Kling·Martin Weitz
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Abstract

We report on an experimental study of quantum transport of atoms in variable periodic optical potentials. The band structure of both ratchet-type asymmetric and symmetric lattice potentials is explored. The variable atom potential is realized by superimposing a conventional standing wave potential of λ/2 spatial periodicity with a fourth-order multiphoton potential of λ/4 periodicity. We find that the Landau-Zener tunneling rate between the first and the second excited Bloch band depends critically on the relative phase between the two spatial lattice harmonics.

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Tobias Salger, Carsten Geckeler, Sebastian Kling, Martin Weitz. 2011-02-28. Atomic Landau-Zener tunneling in Fourier-synthesized optical lattices. https://doi.org/10.1103/physrevlett.99.190405

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