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In the paper, we investigate the transport properties of coupled flashing ratchets in viscoelastic media. Using generalized Langevin equation, subvelocity V α , subdiffusive coefficient D α and generalized Peclet number P e α are calculated as functions of the temperature T and the flashing period τ with different subdiffusive exponents α . The results show that the transport of coupled flashing ratchets can be optimized in viscoelastic media. [ABSTRACT FROM AUTHOR]

Abstract: The transport properties of coupled Brownian particles in a two-dimensional rocking ratchet are investigated via Langevin simulation. The results show that the average center-of-mass velocity is multi-peaks function of the frequency of the driving force. Furthermore, in the 2D coupled Brownian motor system there are the collective effect and ratchet behavior, which can switch depending on the frequency of driving force. It turns out that the cooperative effect between the interaction of coupled particles and external rocking driving force facilitates collective directional motion and energy conversion. [Copyright &y& Elsevier]

Abstract: ATP binding, acting as a gate, plays an important role in kinesin stepping. To understand the physical mechanism of the ATP gate, we propose a Kramers-type elastic ratchet model in which the free head undergoes a biased diffusive search. By first passage time analysis, we investigate the dependence of the mean dwell time on the load force for forward steps of kinesin and find that the forward dwell time varies exponentially with the backward load force which is consistent with the data of Carter and Cross, Nature 435 (2005) 308. Our work suggests that the gating mechanism triggered by ATP binding involves both Kramers-type elastic ratchet mechanism and power stroke movement. [Copyright &y& Elsevier]

Abstract: With this work, we investigate an often neglected aspect of coupled Brownian motors transport, namely, transport coherence. To discuss the transport coherence of coupled Brownian motors, velocity, diffusion coefficient and their ratio (Pe number) are calculated via solving Langevin equation in fluctuating potential ratchet. The results demonstrate that the collective effect of coupled Brownian ratchets can generate high transport coherence. [Copyright &y& Elsevier]

Abstract: The transport properties of coupled Brownian motors in rocking ratchet are investigated via solving Langevin equation analytically and numerically. In comparison with the result of single particle, our results show that the center-of-mass of elastically coupled Brownian motors moves faster than the corresponding single particle, and the efficiency and the Pe number of coupled Brownian motors are larger than those of the single Brownian motor. The reason is that in rocking ratchet the co-operative interplay between the interaction between coupled particles and external nonequilibrium fluctuations facilitates the directed motion and energy conversion. [Copyright &y& Elsevier]

The properties of a ratchet system rectifying the random motion of two harmonically coupled particles with arbitrary coupling strengths are studied via Langevin simulations. In comparison with the result of single particle, our results show that the average center-of-mass velocity vc of two particles is larger than the average velocity v1 of single particle in the rocking ratchet for low-to-moderate noise intensities, however, vc in the flashing ratchet. The former is due to the decrease of effective barrier that the center-of-mass of two particles feels, and the latter is because of the distance of two diffusing particles across the nearest barrier increasing effectively. Numerical results are performed for a larger parameter regime and the validation of the proposed effective potential is illustrated. [Copyright &y& Elsevier]

The directed motion of a Brownian particle subject to a unequilibrium fluctuation which moves in a two-dimensional ratchet potential is studied. Thus, a working model of the free-energy ratchet is proposed through eliminating no-transport variables. The properties of the present model such as the current, the efficiency, the diffusion coefficient and the Pe number are discussed. Comparison with the previous one-dimensional models, some novel phenomena are observed. [Copyright &y& Elsevier]