Overdamped Deterministic Ratchets Driven by Multifrequency Forces∗
نویسندگان
چکیده
We investigate a dissipative, deterministic ratchet model in the overdamped regime driven by a rectangular force. Extensive numerical calculations are presented in a diagram depicting the drift velocity as a function of a wide range of the driving parameter values. We also present some theoretical considerations which explain some features of the mentioned diagram. In particular, we proof the existence of regions in the driving parameter space with bounded particle motion possessing zero current. Moreover, we present an explicit analytical expression for the drift velocity in the adiabatic limit.
منابع مشابه
Deterministic transport in ratchets.
We present the deterministic transport properties of driven overdamped particles in a simple piecewise-linear ratchet potential. We consider the effects on the stationary current due to local spatial asymmetry, time asymmetry in the driving force, and we include the possibility of a global spatial asymmetry. We present an extremely simple scheme for evaluating the current that is established on...
متن کاملAchieving optimal rectification using underdamped rocked ratchets.
An underdamped rocked ratchet operated at very low temperatures and damping is shown: (i) to be capable of rectifying the ac input signal more efficiently than in the overdamped regime; (ii) to be insensitive to the initial conditions, at variance with noiseless, or deterministic, ratchets; and (iii) to be characterized by a wide damping "window," where its efficiency is appreciable also for we...
متن کاملDeterministic Smoluchowski-Feynman ratchets driven by chaotic noise.
We have elucidated the effect of statistical asymmetry on the directed current in Smoluchowski-Feynman ratchets driven by chaotic noise. Based on the inhomogeneous Smoluchowski equation and its generalized version, we arrive at analytical expressions of the directed current that includes a source term. The source term indicates that statistical asymmetry can drive the system further away from t...
متن کاملThe optimal driving waveform for overdamped, adiabatic rocking ratchets
The optimal driving waveform among a wide class of admissible functions for an overdamped, adiabatic rocking ratchet is shown to be dichotomous. ‘Optimum’ is defined as that which achieves the maximum (or minimum negative) average particle velocity. Implications for the design of ratchets, for example in nanotechnological transport, may follow. The main result is applicable to a general class o...
متن کاملOptimal driving waveform for overdamped, adiabatic rocking ratchets
As a first step in the project of ratchet optimisation, the optimal driving waveform among a wide class of admissible functions for an overdamped, adiabatic rocking ratchet is shown to be dichotomous. ‘Optimum’ is defined as that which achieves the maximum (or minimum negative) average particle velocity. Implications for the design of ratchets, for example in nanotechnological transport, may fo...
متن کامل