2007/12/31 by Wolfgang Mauerer, Wolfram Helwig, Christine Silberhorn · 1 citation
Computer Science · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #Quantum Information and Cryptography #quant-ph #stochastic dynamics and bifurcation
paper · pdf · doi:10.1002/andp.200710284
published as Ann. Phys. (Leipzig) 17, No. 2-3, 158, 175 (2008) · Invited paper for the Annals of Physics special issue on the occasion of Max Planck's 150th birthday. This made it inevitable to use Planck, Bohr, and Einstein instead of Alice, Bob, and Eve. Published version with minor corrections
arxiv created 2008/01/29 · openalex publication_date 2008/02/04 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
A flashing ratchet uses a time-dependent, spatially periodic, asymmetric potential to rectify thermal motion of Brownian particles. Here we review approaches to improve the particle flux in this type of Brownian motor by feedback strategies that switch the potential based on the instantaneous particle distribution. We review strategies that are based on the force experienced by the particles, and introduce a new feedback strategy that is based on the expected displacement that can be achieved. Langevin dynamics simulations show that this maximum net displacement strategy performs better than force-based strategies in the limit of very small particle numbers and not too high temperatures. We also review the effects of time delay and noisy channels on feedback control, and perform a feasibility analysis of an experimental system that can realize feedback control using a computer-controlled, scanning-line optical trap and suspended microspheres.