论文标题
在椭圆形胶体悬浮液中观察液体玻璃
Observation of liquid glass in suspensions of ellipsoidal colloids
论文作者
论文摘要
尽管胶体悬浮液无处不在,但对形状对相变的影响知之甚少,尤其是在非平衡中。迄今为止,实际空间成像结果仅限于由球形胶体组成的系统。但是,在大多数天然和技术系统中,粒子是非球形的,其结构动力学是由翻译和旋转自由度决定的。使用共聚焦显微镜,我们揭示了椭圆形胶体的悬浮液形成意外的物质状态,即液体玻璃,其中旋转是冷冻的,而翻译则保持流体。图像分析迄今未知的列神经前体作为该状态的特征结构元素。这些分支的簇的相互阻塞阻止了液晶级。我们的结果为局部结构和相变之间的相互作用提供了独特的见解。这有助于指导诸如胶体上层建筑的自组装等应用,并首先证明了形状对玻璃过渡的重要性。
Despite the omnipresence of colloidal suspensions, little is known about the influence of shape on phase transformations, especially in nonequilibrium. To date, real-space imaging results are limited to systems composed of spherical colloids. In most natural and technical systems, however, particles are non-spherical and their structural dynamics are determined by translational and rotational degrees of freedom. Using confocal microscopy, we reveal that suspensions of ellipsoidal colloids form an unexpected state of matter, a liquid glass in which rotations are frozen while translations remain fluid. Image analysis unveils hitherto unknown nematic precursors as characteristic structural elements of this state. The mutual obstruction of these ramified clusters prevents liquid crystalline order. Our results give unique insight into the interplay between local structures and phase transformations. This helps to guide applications such as self-assembly of colloidal superstructures and also gives first evidence of the importance of shape on the glass transition in general.