Slow dynamics of equilibrium density fluctuations in suspensions of colloidal hard spheres near the glass transition
Slow dynamics of equilibrium density fluctuations in suspensions of colloidal hard spheres near the glass transition
复制标题
玻璃化转变附近胶体硬球悬浮液平衡密度波动的缓慢动力学
DOI：
10.1103/physreve.62.r5915
复制
发表时间：
2000
期刊：
影响因子：
--
通讯作者：
M. Tokuyama
中科院分区：
文献类型：
--
作者：
M. Tokuyama
基于作者最近提出的观点，提出了玻璃化转变附近胶体硬球平衡悬浮液动力学的平均场理论。结果表明，即使在玻璃化转变附近，密度涨落相对于平均平衡密度的相对大小也很小，但它们可以用一个源于粒子间长程流体动力相互作用的非线性随机方程来描述。在此基础上，导出了质点均方位移的非线性平均场方程。用该方程分析了平衡胶体悬浮液的最新实验数据。分析表明，尽管胶体液体的动力学性质在所谓的过冷区表现出剧烈的减慢，但在实验数据中没有发现α和β弛豫时间的发散。
A mean-field theory for the dynamics of equilibrium suspensions of colloidal hard spheres near the glass transition is presented based on the standpoint recently proposed by the present author. It is shown that although the relative magnitude of the density fluctuations to the mean equilibrium density is small even near the glass transition, they are described by a nonlinear stochastic equation which originates from the long-range hydrodynamic interactions between particles. A nonlinear mean-field equation for the particle mean-square displacement is then derived. This equation is used to analyze the recent experimental data for equilibrium colloidal suspensions. Analyses show that no divergence of the alpha- and beta-relaxation times is found in the experimental data, although the dynamic properties of the colloidal liquid exhibit a drastic slowing down in the so-called supercooled region.