2008/07/31 by Benjamin J. Lopez, Nathan J. Kuwada, Erin M. Craig +2 · 1 citation
Physics and Astronomy · #cond-mat.stat-mech
paper · pdf · doi:10.1103/physrevlett.101.220601
published as PhysRevLett.101.220601 (2008)
arxiv created 2008/09/26 · arxiv updated 2009/12/01
A flashing ratchet transports diffusive particles using a time-dependent, asymmetric potential. Particle speed is predicted to increase when a feedback algorithm based on particle positions is used. We have experimentally realized such a feedback ratchet using an optical line trap, and observed that use of feedback increases velocity by up to an order of magnitude. We compare two different feedback algorithms for small particle numbers, and find good agreement with simulations. We also find that existing algorithms can be improved to be more tolerant to feedback delay times.