Zhang Rui, Mozaffari Ali, de Pablo Juan J
Pritzker School of Molecular Engineering, University of Chicago, Chicago, IL 60637, USA.
Department of Physics, Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR.
Sci Adv. 2022 Feb 25;8(8):eabg9060. doi: 10.1126/sciadv.abg9060. Epub 2022 Feb 23.
Logic operations performed by semiconductor-based transistors are the basis of modern computing. There is considerable interest in creating autonomous materials systems endowed with the capability to make decisions. In this work, we introduce the concept of using topological defects in active matter to perform logic operations. When an extensile active stress in a nematic liquid crystal is turned on, +1/2 defects can self-propel, in analogy to electron transport under a voltage gradient. By relying on hydrodynamic simulations of active nematics, we demonstrate that patterns of activity, when combined with surfaces imparting certain orientations, can be used to control the formation and transport of +1/2 defects. We further show that asymmetric high- and low-activity patterns can be used to create effective defect gates, tunnels, and amplifiers. The proposed active systems offer the potential to perform computations and transmit information in active soft materials, including actin-, tubulin-, and cell-based systems.
基于半导体的晶体管所执行的逻辑运算，是现代计算的基础。人们对创建具有决策能力的自主材料系统有着浓厚的兴趣。在这项工作中，我们引入了利用活性物质中的拓扑缺陷来执行逻辑运算的概念。当向向列型液晶施加拉伸活性应力时，+1/2缺陷能够自行推进，这类似于在电压梯度下的电子传输。通过依赖活性向列相的流体动力学模拟，我们证明，当活性模式与赋予特定取向的表面相结合时，可用于控制+1/2缺陷的形成和传输。我们进一步表明，不对称的高活性和低活性模式可用于创建有效的缺陷门、隧道和放大器。所提出的活性系统具有在活性软材料（包括基于肌动蛋白、微管蛋白和细胞的系统）中执行计算和传输信息的潜力。
