Malgaretti Paolo, Pagonabarraga Ignacio, Rubí J Miguel
Department de Fisica Fonamental, Universitat de Barcelona, Barcelona, Spain.
Phys Rev E Stat Nonlin Soft Matter Phys. 2012 Jan;85(1 Pt 1):010105. doi: 10.1103/PhysRevE.85.010105. Epub 2012 Jan 20.
We analyze the rectified motion of a Brownian particle in a confined environment. We show the emergence of strong cooperativity between the inherent rectification of the ratchet mechanism and the entropic bias of the fluctuations caused by spatial confinement. Net particle transport may develop even in situations where separately the ratchet and the geometric restrictions do not give rise to particle motion. The combined rectification effects can lead to bidirectional transport depending on particle size, resulting in a different route for segregation. The reported mechanism can be used to control transport in mesostructures and nanodevices in which particles move in a reduced space.
我们分析了受限环境中布朗粒子的整流运动。我们展示了棘轮机制的固有整流与空间限制引起的涨落的熵偏置之间强烈协同作用的出现。即使在棘轮和几何限制单独都不会导致粒子运动的情况下，净粒子输运也可能发生。组合的整流效应可导致取决于粒子大小的双向输运，从而产生不同的分离途径。所报道的机制可用于控制介观结构和纳米器件中的输运，其中粒子在受限空间中移动。
