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Phase-control of directed diffusion in a symmetric optical lattice

Michele Schiavoni·Laurent Sanchez-Palencia·Ferruccio Renzoni·Gilbert Grynberg
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Abstract

We demonstrate the phenomenon of directed diffusion in a symmetric periodic potential. This has been realized with cold atoms in a one-dimensional dissipative optical lattice. The stochastic process of optical pumping leads to a diffusive dynamics of the atoms through the periodic structure, while a zero-mean force which breaks the temporal symmetry of the system is applied by phase-modulating one of the lattice beams. The atoms are set into directed motion as a result of the breaking of the temporal symmetry of the system.

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Michele Schiavoni, Laurent Sanchez-Palencia, Ferruccio Renzoni, Gilbert Grynberg. 2003-09-29. Phase-control of directed diffusion in a symmetric optical lattice. https://doi.org/10.1103/physrevlett.90.094101

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