论文标题
机械化学活动棘轮
Mechanochemical Active Ratchet
论文作者
论文摘要
自propell的纳米颗粒在液体中移动,可以创建高级应用,在这种应用中,这种纳米晶体可以用作人工分子大小的电机。控制纳米晶体器的运动是其可靠功能的关键方面。虽然可以很好地控制微米大小的游泳者的方向性,但转向纳米大小的活性颗粒却带来了真正的挑战。原因之一是在纳米级存在很大的主动速度波动。在这里,我们描述了一种机制,在存在棘轮电势的情况下,将这些波动转化为活性纳米颗粒的净电流。我们使用由化学反应驱动的自我刺激的通用模型证明了效果。沿棘轮电势的简易方向的净运动来自化学和机械过程的耦合,并由恒定的横向到棘轮,力触发。当前的幅度敏感地取决于棘轮电势的振幅和周期性和横向力的强度。我们的结果强调了热力学在纳米级活动物质中化学反应建模的重要性,并提出了控制这种系统中动力学的新方法。
Self-propelled nanoparticles moving through liquids offer the possibility of creating advanced applications where such nanoswimmers can operate as artificial molecular-sized motors. Achieving control over the motion of nanoswimmers is a crucial aspect for their reliable functioning. While the directionality of micron-sized swimmers can be controlled with great precision, steering nano-sized active particles poses a real challenge. One of the reasons is the existence of large fluctuations of active velocity at the nanoscale. Here, we describe a mechanism that, in the presence of a ratchet potential, transforms these fluctuations into a net current of active nanoparticles. We demonstrate the effect using a generic model of self-propulsion powered by chemical reactions. The net motion along the easy direction of the ratchet potential arises from the coupling of chemical and mechanical processes and is triggered by a constant, transverse to the ratchet, force. The current magnitude sensitively depends on the amplitude and the periodicity of the ratchet potential and the strength of the transverse force. Our results highlight the importance of thermodynamically consistent modeling of chemical reactions in active matter at the nanoscale and suggest new ways of controlling dynamics in such systems.