论文标题
噪声抑制揭示的布朗动力学模拟中的持续反相关模拟
Persistent anti-correlations in Brownian dynamics simulations of dense colloidal suspensions revealed by noise suppression
论文作者
论文摘要
通过布朗动力学模拟研究了硬球胶体流体的转运性能。我们为时间依赖性速度自动相关函数（VACF）实现了一种新型算法，从本质上消除了裸露随机运动的噪声。测得的交接揭示了所有密度的负代数幂律尾巴$ t^{ - 5/2} $所表现出的持续反相关。在小堆积分数下，模拟完全与分析性低密度预测完全一致，但是随着填料分数的增加，尾巴的振幅受到了极大的抑制。玻璃转变的模式耦合理论为静态可压缩性以及结构放松的降低提供了质量差异的定性解释。
Transport properties of a hard-sphere colloidal fluid are investigated by Brownian dynamics simulations. We implement a novel algorithm for the time-dependent velocity-autocorrelation function (VACF) essentially eliminating the noise of the bare random motion. The measured VACF reveals persistent anti-correlations manifested by a negative algebraic power-law tail $t^{-5/2}$ at all densities. At small packing fractions, the simulations fully agree with the analytic low-density prediction, yet the amplitude of the tail becomes dramatically suppressed as the packing fraction is increased. The mode-coupling theory of the glass transition provides a qualitative explanation for the strong variation in terms of the static compressibility as well as the slowing down of the structural relaxation.
