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arXiv · 1210.6025

Controlling the Momentum Current of an Off-resonant Ratchet

R. K. Shrestha·J. Ni·W. K. Lam·S. Wimberger·G. S. Summy
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Abstract

We experimentally investigate the phenomenon of a quantum ratchet created by exposing a Bose-Einstein Condensate to short pulses of a potential which is periodic in both space and time. Such a ratchet is manifested by a directed current of particles, even though there is an absence of a net bias force. We confirm a recent theoretical prediction [M. Sadgrove and S. Wimberger, New J. Phys. \textbf{11}, 083027 (2009)] that the current direction can be controlled by experimental parameters which leave the underlying symmetries of the system unchanged. We demonstrate that this behavior can be understood using a single variable containing many of the experimental parameters and thus the ratchet current is describable using a single universal scaling law.

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R. K. Shrestha, J. Ni, W. K. Lam, S. Wimberger, G. S. Summy. 2012-10-20. Controlling the Momentum Current of an Off-resonant Ratchet. https://doi.org/10.1103/physreva.86.043617

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