arXiv:1111.6520 · Physical Review A

Two-dimensional rocking ratchet for cold atoms

V. Lebedev, Ferruccio Renzoni

Published Aug 27, 2009• 22 citations

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, Y. Zolotaryuk, S. Flach, and O. Yevtushenko, 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 biharmonic forces in perpendicular directions, we demonstrate the possibility of generating a current in an arbitrary direction within the optical lattice plane.

DOI: 10.1103/physreva.80.023422

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