Yoshida Masaki, Mizuno Hideyuki, Ikeda Atsushi
Graduate School of Arts and Sciences, The University of Tokyo, Tokyo 153-8902, Japan.
Research Center for Complex Systems Biology, Universal Biology Institute, The University of Tokyo, Tokyo 153-8902, Japan.
Soft Matter. 2024 Oct 2;20(38):7678-7691. doi: 10.1039/d4sm00821a.
The glassy dynamics of dense active matter have recently become a topic of interest due to their importance in biological processes such as wound healing and tissue development. However, while the liquid-state properties of dense active matter have been studied in relation to the glass transition of active matter, the solid-state properties of active glasses have yet to be understood. In this work, we study the structural fluctuations in the active glasses composed of self-propelled particles. We develop a formalism to describe the solid-state properties of active glasses in the harmonic approximation limit and use it to analyze the displacement fields in the active glasses. Our findings reveal that the dynamics of high-frequency normal modes become quasi-static with respect to the active forces, and consequently, excitations of these modes are significantly suppressed. This leads to a violation of the equipartition law, suppression of particle displacements, and the apparent collective motion of active glasses. Overall, our results provide a fundamental understanding of the solid-state properties of active glasses.
由于其在伤口愈合和组织发育等生物过程中的重要性，致密活性物质的玻璃态动力学最近成为一个研究热点。然而，尽管已经研究了致密活性物质的液态性质与活性物质玻璃化转变的关系，但活性玻璃的固态性质仍有待了解。在这项工作中，我们研究了由自推进粒子组成的活性玻璃中的结构涨落。我们发展了一种形式理论来描述在简谐近似极限下活性玻璃的固态性质，并利用它来分析活性玻璃中的位移场。我们的研究结果表明，高频正则模式的动力学相对于活性力变得准静态，因此，这些模式的激发被显著抑制。这导致了均分定律的违反、粒子位移的抑制以及活性玻璃明显的集体运动。总体而言，我们的结果为活性玻璃的固态性质提供了基本的理解。
