论文标题
通过弯曲的瓶颈扩散场驱动的示踪剂：第一通道事件的精细结构
Field-driven tracer diffusion through curved bottlenecks: Fine structure of first passage events
论文作者
论文摘要
使用缩放参数和广泛的数值模拟，我们研究了瓦楞通道中示踪剂粒子的动力学，该动力学由宽室的周期序列和狭窄的漏斗样瓶颈表示，被硬墙边界包含。示踪剂粒子受沿通道指向的外力的影响，并在垂直方向上执行无偏扩散。我们提供了一个详细的分析a）高度上方的高度分布函数，在该边界上，在该边界上进行了第一次交叉的交叉，以及b）第一个通道时间到此类事件的分布函数。我们的分析揭示了动力学行为的几个新特征，这些特征在研究中基于Fick-Jacobs方法而忽略了。特别是，穿过漏斗的轨迹主要集中在其边界上，这使得第一次跨事件对结合位点的存在和显微镜粗糙度非常敏感。
Using scaling arguments and extensive numerical simulations, we study dynamics of a tracer particle in a corrugated channel represented by a periodic sequence of broad chambers and narrow funnel-like bottlenecks enclosed by a hard-wall boundary. A tracer particle is affected by an external force pointing along the channel, and performs an unbiased diffusion in the perpendicular direction. We present a detailed analysis a) of the distribution function of the height above the funnel's boundary at which the first crossing of a given bottleneck takes place, and b) of the distribution function of the first passage time to such an event. Our analysis reveals several new features of the dynamical behaviour which are overlooked in the studies based on the Fick-Jacobs approach. In particular, trajectories passing through a funnel concentrate predominantly on its boundary, which makes first-crossing events very sensitive to the presence of binding sites and a microscopic roughness.
