6533b821fe1ef96bd127b083

RESEARCH PRODUCT

Active Brownian Motion Models and Applications to Ratchets

Werner EbelingEwa Gudowska-nowakAlessandro Fiasconaro

subject

PhysicsStatistical Mechanics (cond-mat.stat-mech)RatchetPerturbation (astronomy)FOS: Physical sciencesFluctuation phenomena random processes noise Brownian motion Nonlinear dynamics and chaosWhite noiseCondensed Matter - Soft Condensed MatterCondensed Matter PhysicsKinetic energyElectronic Optical and Magnetic MaterialsClassical mechanicsPhysics - Data Analysis Statistics and ProbabilityMolecular motorDirectionalitySoft Condensed Matter (cond-mat.soft)Differentiable functionBrownian motionData Analysis Statistics and Probability (physics.data-an)Condensed Matter - Statistical Mechanics

description

We give an overview over recent studies on the model of Active Brownian Motion (ABM) coupled to reservoirs providing free energy which may be converted into kinetic energy of motion. First, we present an introduction to a general concept of active Brownian particles which are capable to take up energy from the source and transform part of it in order to perform various activities. In the second part of our presentation we consider applications of ABM to ratchet systems with different forms of differentiable potentials. Both analytical and numerical evaluations are discussed for three cases of sinusoidal, staircase-like and Mateos ratchet potentials, also with the additional loads modeled by tilted potential structure. In addition, stochastic character of the kinetics is investigated by considering perturbation by Gaussian white noise which is shown to be responsible for driving the directionality of the asymptotic flux in the ratchet. This \textit{stochastically driven directionality} effect is visualized as a strong nonmonotonic dependence of the statistics of the right versus left trajectories of motion leading to a net current of particles. Possible applications of the ratchet systems to molecular motors are also briefly discussed

10.1140/epjb/e2008-00267-9http://arxiv.org/abs/0801.4838