Directed transport driven by Lévy flights coexisting with subdiffusion
arXiv:1003.3709 · doi:10.1063/1.3327842
Abstract
Transport of the Brownian particles driven by Lévy flights coexisting with subdiffusion in asymmetric periodic potentials is investigated in the absence of any external driving forces. Using the Langevin-type dynamics with subordination techniques, we obtain the group velocity which can measure the transport. It is found that the group velocity increases monotonically with the subdiffusive index and there exists an optimal value of the Lévy index at which the group velocity takes its maximal value. There is a threshold value of the subdiffusive index below which the ratchet effects will disappear. The nonthermal character of the Lévy flights and the asymmetry of the potential are necessary to obtain the directed transport. Some peculiar phenomena induced by the competition between Lévy flights and subdiffusion are also observed. The pseudonormal diffusion will appear on the level of the median.
6 figures
References in corpus (5)
- Artificial Brownian motors: Controlling transport on the nanoscale
- Current in a three-dimensional periodic tube with unbiased forces
- Fractional Fokker-Planck dynamics: Numerical algorithm and simulations
- Transport in a Levy ratchet: Group velocity and distribution spread
- ac-driven Brownian motors: a Fokker-Planck treatment