标题： 碰撞增强活性Janus浴中的示踪扩散性 显示英文标题

标题： Collisions enhance tracer diffusivity in an active Janus bath

摘要： 由自促微泳器产生的流体流动被提出作为一种机制，以增强微观和纳米尺度的质量传输。 在这里，我们实验研究了模型“活性浴”光催化二氧化硅-二氧化钛Janus微球在排除集体效应的情况下，增强不同微泳器密度下示踪粒子扩散率的能力。 受我们实验结果与之前生物微生物结果之间相似性的启发，我们还使用一般的Squirmer框架对我们的Janus微泳器进行建模。 数值模拟准确地捕捉了我们的观察结果，提供了对示踪粒子传输微观机制的见解，并使我们能够扩展超出我们实验系统的参数空间。 我们发现有强有力的证据表明，增加的示踪粒子扩散率是基于碰撞的机制，这导致了基于无量纲尺度论证的化学微泳器增强示踪粒子传输的操作窗口的确定。 显示英文摘要

摘要： The generation of fluid flows by autophoretic microswimmers has been proposed as a mechanism to enhance mass transport at the micro- and nanoscale. Here, we experimentally investigate the ability of model "active baths" of photocatalytic silica-titania Janus microspheres to enhance the diffusivity of tracer particles at different microswimmer densities excluding collective effects. Inspired by the similarities between our experimental findings and previous results for biological microorganisms, we also model our Janus microswimmers using a general squirmer framework. The numerical simulations faithfully capture our observations, offer an insight into the microscopic mechanism underpinning tracer transport, and allow us to expand the parameter space beyond our experimental system. We find strong evidence for a collision-based mechanism for increased tracer diffusivity, which leads to the identification of an operating window for enhanced tracer transport by chemical microswimmers based on dimensionless scaling arguments.