标题： 在低温下，玻璃形成液体以简单的方式松弛 显示英文标题

标题： At low temperatures, glass-forming liquids relax in a simple way

摘要： 玻璃形成液体只有适度的结晶倾向，因此即使在熔点以下也可以研究其动力学。 这些液体的弛豫动力学在温度$T_c$时表现出一种交叉现象，该温度略高于玻璃转变温度$T_g$，表明了两种不同动力学区间的结合。 对于略高于$T_c$的温度，实验和计算机模拟已在粒子层面上广泛研究了这种动力学，并确定了几种普遍的标度定律，这些定律通常与理论预测相容。 使用大规模的计算机模拟，我们将这些研究扩展到低于$T_c$的温度，并发现弛豫机制与较高温度下的机制有本质的不同。 我们确定了新的标度定律，这些定律可以对非常低的$T$下的弛豫动力学进行简单的描述。 具体而言，我们揭示了笼子逃逸过程与罕见但大的粒子位移有关，这些位移在时间相关函数中产生了独特的亚扩散幂律。 这一见解有助于加深我们对接近实验玻璃转变温度的玻璃形成系统弛豫动力学的理解。 显示英文摘要

摘要： Glass-forming liquids have only a modest tendency to crystallize and hence their dynamics can be studied even below the melting temperature. The relaxation dynamics of most of these liquids shows at a temperature $T_c$, somewhat above the glass-transition temperature $T_g$, a crossover, which indicates the conjunction of two different dynamical regimes. For temperatures slightly above $T_c$, experiments and computer simulations have extensively probed this dynamics on the particle level and identified several universal scaling laws that are often compatible with theoretical predictions. Using large scale computer simulations we extend these studies to temperatures below $T_c$ and find that the relaxation mechanism is qualitatively different from the one found at higher temperatures. We identify new scaling laws that allow to give a simple description of the relaxation dynamics at very low $T$s. Specifically we reveal that the cage-escape process is related to rare but large particle displacements that give rise to a distinctive sub-diffusive power-law in the time correlation functions. This insight helps to advance our understanding on the relaxation dynamics of glass-forming systems at temperatures that are close to the experimental glass transition.