Fins Carreira Adérito, Wysocki Adam, Ybert Christophe, Leocmach Mathieu, Rieger Heiko, Cottin-Bizonne Cécile
Université de Lyon, Université Claude Bernard Lyon 1, CNRS, Institut Lumière Matière, Villeurbanne, France.
Department of Theoretical Physics and Center for Biophysics, Saarland University, Saarbrücken, Germany.
Nat Commun. 2024 Feb 24;15(1):1710. doi: 10.1038/s41467-024-45872-1.
An important challenge in active matter lies in harnessing useful global work from entities that produce work locally, e.g., via self-propulsion. We investigate here the active matter version of a classical capillary rise effect, by considering a non-phase separated sediment of self-propelled Janus colloids in contact with a vertical wall. We provide experimental evidence of an unexpected and dynamic adsorption layer at the wall. Additionally, we develop a complementary numerical model that recapitulates the experimental observations. We show that an adhesive and aligning wall enhances the pre-existing polarity heterogeneity within the bulk, enabling polar active particles to climb up a wall against gravity, effectively powering a global flux. Such steady-state flux has no equivalent in a passive wetting layer.
活性物质研究中的一个重要挑战在于，如何从那些在局部产生功的实体（例如通过自推进）中获取有用的整体功。我们在此研究经典毛细上升效应的活性物质版本，方法是考虑一种与垂直壁接触的自推进Janus胶体的非相分离沉积物。我们提供了壁上存在意外动态吸附层的实验证据。此外，我们开发了一个补充性数值模型，该模型概括了实验观察结果。我们表明，具有粘附性和取向性的壁增强了整体中预先存在的极性异质性，使极性活性粒子能够克服重力爬上壁，从而有效地驱动整体通量。这种稳态通量在被动润湿层中并不存在。
