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Many-body quantum ratchet in a Bose-Einstein condensate

Dario Poletti·Giuliano Benenti·Giulio Casati·Baowen Li
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Abstract

We study the dynamics of a dilute Bose-Einstein condensate confined in a toroidal trap and exposed to a pair of periodically flashed optical lattices. We first prove that in the noninteracting case this system can present a quantum symmetry which forbids the ratchet effect classically expected. We then show how many-body atom-atom interactions, treated within the mean-field approximation, can break this quantum symmetry, thus generating directed transport.

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Dario Poletti, Giuliano Benenti, Giulio Casati, Baowen Li. 2006-09-21. Many-body quantum ratchet in a Bose-Einstein condensate. https://doi.org/10.1103/physreva.76.023421

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