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Directed motion for delta-kicked atoms with broken symmetries: comparison between theory and experiment
P H Jones1, M Goonasekera, D R Meacher
1Department of Physics and Astronomy, University College London, Gower Street, London WC1E 6BT, United Kingdom.
Abstract:
We report an experimental investigation of momentum diffusion in the delta-function kicked rotor where time symmetry is broken by a two-period kicking cycle and spatial symmetry by an alternating linear potential. We exploit this, and a technique involving a moving optical potential, to create an asymmetry in the momentum diffusion that is due to the classical chaotic diffusion. This represents a realization of a type of Hamiltonian quantum ratchet.
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