arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1408.4645cond-mat.soft
收藏

二维软球无序拥挤堆积的超均匀性诊断

Diagnosing hyperuniformity in two-dimensional disordered jammed-packings of soft spheres

Remi Dreyfus, Ye Xu, Tim Still, Lawrence A. Hough, A. G. Yodh, Salvatore Torquato

摘要:

超均匀性是物质的一种状态,在这种状态下,密度波动在最大的长度尺度上趋于零。然而,确定实验系统是否是超均匀的任务在实验上是具有挑战性的,由于有限的分辨率,噪声和样本大小的影响表征测量的效果。在这里,我们探讨这些问题,采用视频光学显微镜研究超均匀性现象在无序的二维堵塞包装的软球。使用实验和模拟相结合,我们的颗粒多分散性,图像噪声和有限尺寸的影响分配的超均匀性的有害影响的特征,我们开发了一种方法,允许改善诊断超均匀性从真实空间测量。这种改进的关键是一个简单的包装重建算法,结合粒子多分散性,以尽量减少自由体积。此外,仿真结果表明,超均匀性可以更准确地确定在直接空间比在倒易空间作为一个有限的样本容量的结果。最后,软聚合物球的实验胶体填料被证明是超均匀的。

英文摘要:

Hyperuniformity characterizes a state of matter for which density fluctuations diminish towards zero at the largest length scales. However, the task of determining whether or not an experimental system is hyperuniform is experimentally challenging due to finite-resolution, noise and sample-size effects that influence characterization measurements. Here we explore these issues, employing video optical microscopy to study hyperuniformity phenomena in disordered two-dimensional jammed packings of soft spheres. Using a combination of experiment and simulation we characterize the detrimental effects of particle polydispersity, image noise, and finite-size effects on the assignment of hyperuniformity, and we develop a methodology that permits improved diagnosis of hyperuniformity from real-space measurements. The key to this improvement is a simple packing reconstruction algorithm that incorporates particle polydispersity to minimize free volume. In addition, simulations show that hyperuniformity can be ascertained more accurately in direct space than in reciprocal space as a result of finite sample-size. Finally, experimental colloidal packings of soft polymeric spheres are shown to be hyperuniform.

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。

↑