TY  - JOUR
A1  - Goychuk, I.
A1  - Kharchenko, V. O.
T1  - Rocking subdiffusive ratchets origin, optimization and efficiency
JF  - Mathematical modelling of natural phenomena
N2  - We study origin, parameter optimization, and thermodynamic efficiency of isothermal rocking ratchets based on fractional subdiffusion within a generalized non-Markovian Langevin equation approach. A corresponding multi-dimensional Markovian embedding dynamics is realized using a set of auxiliary Brownian particles elastically coupled to the central Brownian particle (see video on the journal web site). We show that anomalous subdiffusive transport emerges due to an interplay of nonlinear response and viscoelastic effects for fractional Brownian motion in periodic potentials with broken space-inversion symmetry and driven by a time-periodic field. The anomalous transport becomes optimal for a subthreshold driving when the driving period matches a characteristic time scale of interwell transitions. It can also be optimized by varying temperature, amplitude of periodic potential and driving strength. The useful work done against a load shows a parabolic dependence on the load strength. It grows sublinearly with time and the corresponding thermodynamic efficiency decays algebraically in time because the energy supplied by the driving field scales with time linearly. However, it compares well with the efficiency of normal diffusion rocking ratchets on an appreciably long time scale.
KW  - anomalous Brownian motion
KW  - generalized Langevin equation
KW  - memory effects
KW  - viscoelasticity
KW  - ratchet transport
KW  - stochastic thermodynamics
Y1  - 2013
U6  - https://doi.org/10.1051/mmnp/20138210
SN  - 0973-5348
VL  - 8
IS  - 2
SP  - 144
EP  - 158
PB  - EDP Sciences
CY  - Les Ulis
ER  -