随机中心耦合布朗马达的定向输运与随机共振

Directed transport and stochastic resonance in centralized coupled Brownian motors with stochastic interactions

摘要:

在一些物理和生物环境中, 耦合布朗粒子因受介质的温度、浓度等的影响而与周围粒子作用，产生不同程度的粘附和脱落过程, 其中便伴随着关联结构的随机解耦合和再耦合行为. 本文基于Langevin方程引入了一种新的具有中心随机耦合结构的布朗马达模型来刻画系统输运过程中环境粒子与中心粒子间以一定概率发生局部弹性耦合作用, 并形成关联粒子数的随机涨落. 仿真结果表明, 耦合系统的结构参数、势场对称性及噪声强度等对粒子输运行为均产生显著影响, 并且可以观察到系统协作、随机共振和广义随机共振等现象.

Abstract:

In some physical or biological environments, the surrounding medium contains many particles of the same kind as coupled Brownian particles capable of not only decoupling from the original coupled system but also adhering to each other and recoupling a larger system. Thus a mathematical model is proposed based on Langevin equations (LEs) to characterize the random interactions with fluctuating number of Brownian particles in the centralized coupled system. By the system simulations, the effects of interacting parameters, ratchet asymmetry and noisy intensity on collective transport behaviors are investigated, and some phenomena, such as cooperative behaviors, stochastic resonance (SR) and generalized SR, are observed.