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arXiv · 1111.6520

Two-dimensional rocking ratchet for cold atoms

V. Lebedev·F. Renzoni
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Abstract

We investigate experimentally a two-dimensional rocking ratchet for cold atoms, realized by using a driven three-beam dissipative optical lattice. AC forces are applied in perpendicular directions by phase-modulating two of the lattice beams. As predicted by the general theory [S. Denisov et al., Phys. Rev. Lett. 100, 224102 (2008)], we observe a rectification phenomenon unique to high-dimensional rocking ratchets, as determined by two single-harmonic drivings applied in orthogonal directions. Also, by applying two bi-harmonic forces in perpendicular directions, we demonstrate the possibility of generating a current in an arbitrary direction within the optical lattice plane.

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V. Lebedev, F. Renzoni. 2011-11-28. Two-dimensional rocking ratchet for cold atoms. https://doi.org/10.1103/physreva.80.023422

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