Xia Chengjie, Li Jindong, Cao Yixin, Kou Binquan, Xiao Xianghui, Fezzaa Kamel, Xiao Tiqiao, Wang Yujie
Department of Physics and Astronomy, Shanghai Jiao Tong University, 800 Dong Chuan Road, Shanghai 200240, China.
Advanced Photon Source, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA.
Nat Commun. 2015 Sep 28;6:8409. doi: 10.1038/ncomms9409.
Glass transition is accompanied by a rapid growth of the structural relaxation time and a concomitant decrease of configurational entropy. It remains unclear whether the transition has a thermodynamic origin, and whether the dynamic arrest is associated with the growth of a certain static order. Using granular packing as a model hard-sphere glass, we show the glass transition as a thermodynamic phase transition with a 'hidden' polytetrahedral order. This polytetrahedral order is spatially correlated with the slow dynamics. It is geometrically frustrated and has a peculiar fractal dimension. Additionally, as the packing fraction increases, its growth follows an entropy-driven nucleation process, similar to that of the random first-order transition theory. Our study essentially identifies a long-sought-after structural glass order in hard-sphere glasses.
玻璃化转变伴随着结构弛豫时间的迅速增长以及构型熵的相应降低。目前尚不清楚这种转变是否具有热力学起源，以及动力学阻滞是否与某种静态有序的增长相关。我们将颗粒堆积作为硬球玻璃的模型，证明玻璃化转变是一种具有“隐藏”多面体有序的热力学相变。这种多面体有序在空间上与慢动力学相关。它在几何上是受挫的，并且具有独特的分形维数。此外，随着堆积分数的增加，其增长遵循熵驱动的成核过程，类似于随机一级转变理论中的情况。我们的研究本质上确定了硬球玻璃中长期以来寻找的结构玻璃有序。
