arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1608.04853cond-mat.soft
收藏

二维随机受限胶体流体的动力学非均匀性和非高斯行为

Dynamic heterogeneities and non-Gaussian behavior in two-dimensional randomly confined colloidal fluids

Simon K. Schnyder, Thomas O. E. Skinner, Alice L. Thorneywork, Dirk G. A. L. Aarts, Jürgen Horbach, Roel P. A. Dullens

摘要:

超顺磁性胶体颗粒的二元混合物被限制在玻璃板之间,使得大颗粒变得固定,并为仍然移动的小颗粒提供二维无序基质,其形成流体。通过改变流体和基质面积分数,并通过外部磁场调节超顺磁性颗粒之间的相互作用,探索了状态图的不同区域。移动粒子在小的基质面积分数下表现出离域动力学,在高的基质面积分数下表现出局域运动,并且局域化转变被软相互作用圆化[T. O. E. Skinner等人,Phys.Rev.Lett. { \bf 111},128301(2013)]。扩展以前的工作,我们发现的动力学示踪剂是强烈的异质性,并表明,分子动力学模拟的理想气体局限在一个固定的矩阵表现出类似的行为。模拟显示了这些软相互作用如何使动力学比无序洛伦兹气体更不均匀,并导致强烈的非高斯波动。

英文摘要:

A binary mixture of super-paramagnetic colloidal particles is confined between glass plates such that the large particles become fixed and provide a two-dimensional disordered matrix for the still mobile small particles, which form a fluid. By varying fluid and matrix area fractions and tuning the interactions between the super-paramagnetic particles via an external magnetic field, different regions of the state diagram are explored. The mobile particles exhibit delocalized dynamics at small matrix area fractions and localised motion at high matrix area fractions, and the localization transition is rounded by the soft interactions [T. O. E. Skinner et al, Phys. Rev. Lett. {\bf 111}, 128301 (2013)]. Expanding on previous work, we find the dynamics of the tracers to be strongly heterogeneous and show that molecular dynamics simulations of an ideal gas confined in a fixed matrix exhibit similar behavior. The simulations show how these soft interactions make the dynamics more heterogenous compared to the disordered Lorentz gas and lead to strong non-Gaussian fluctuations.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑