6533b7d4fe1ef96bd12627ce
RESEARCH PRODUCT
Diffusion in Flashing Periodic Potentials
Alexander A. DubkovBernardo Spagnolosubject
PhysicsFluctuating Rectangular Periodic PotentialStatistical Mechanics (cond-mat.stat-mech)Mathematical analysisFOS: Physical sciencesSawtooth waveCondensed Matter - Soft Condensed MatterCondensed Matter PhysicsNoise (electronics)Electronic Optical and Magnetic Materialssymbols.namesakeAccelerationAdditive white Gaussian noisesymbolsSoft Condensed Matter (cond-mat.soft)Effective diffusion coefficientDiffusion (business)First-hitting-time modelBrownian motionCondensed Matter - Statistical Mechanicsdescription
The one-dimensional overdamped Brownian motion in a symmetric periodic potential modulated by external time-reversible noise is analyzed. The calculation of the effective diffusion coefficient is reduced to the mean first passage time problem. We derive general equations to calculate the effective diffusion coefficient of Brownian particles moving in arbitrary supersymmetric potential modulated: (i) by external white Gaussian noise and (ii) by Markovian dichotomous noise. For both cases the exact expressions for the effective diffusion coefficient are derived. We obtain acceleration of diffusion in comparison with the free diffusion case for fast fluctuating potentials with arbitrary profile and for sawtooth potential in case (ii). In this case the parameter region where this effect can be observed is given. We obtain also a finite net diffusion in the absence of thermal noise. For rectangular potential the diffusion slows down in comparison with the case when particles diffuse freely, for all parameters of noise and of potential.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2005-10-07 |