Coherent ratchets in driven Bose-Einstein condensates
arXiv:0908.0692 · doi:10.1103/PhysRevLett.103.200601
Abstract
We study the response of a Bose-Einstein condensate to an unbiased periodic driving potential. By controlling the space and time symmetries of the driving we show how a directed current can be induced, producing a coherent quantum ratchet. Weak driving induces a regular behavior that is strongly governed by the interparticle interaction. Breaking both space and time symmetries is required to produce current flow. For strong driving the behavior becomes chaotic. The resulting effective irreversibility renders the space asymmetry sufficient to produce the ratchet effect, although the system is completely coherent.
5 pages, 4 eps figures. Minor changes, this version to be published in PRL
References in corpus (11)
- Artificial Brownian motors: Controlling transport on the nanoscale
- Observation of persistent flow of a Bose-Einstein condensate in a toroidal trap
- Experimental Realization of Quantum-Resonance Ratchets
- Periodically driven Quantum Ratchets: Symmetries and Resonances
- Rectified momentum transport for a kicked Bose-Einstein Condensate
- Cold atom confinement in an all-optical dark ring trap
- Steering Bose-Einstein condensates despite time symmetry
- Dynamical instability in kicked Bose-Einstein condensates: Bogoliubov resonances
- Many-body quantum ratchet in a Bose-Einstein condensate
- Time reversal of Bose-Einstein condensates
- Transport phenomena in the asymmetric quantum multibaker map