Entropy-driven atomic activation in supercooled liquids and its link to the fragile-to-strong transition
Entropy-driven atomic activation in supercooled liquids and its link to the fragile-to-strong transition
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DOI：
10.1007/s11433-022-2061-2
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发表时间：
2023-03
期刊：
影响因子：
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通讯作者：
Wei Chu;Zheng Wang;N. Ren;B. Dong;Jinhua Yu;P. Guan;Yanhui Liu;Y. Yue;Lina Hu
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文献类型：
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作者：
Wei Chu;Zheng Wang;N. Ren;B. Dong;Jinhua Yu;P. Guan;Yanhui Liu;Y. Yue;Lina Hu
作为玻璃形成液体（GFL）中常见但关键的动态交叉，脆到强（F-S）转变的发现为理解过冷液体和玻璃化转变提供了一条新途径。目前的工作首次成功实现了九种金属玻璃形成液体中 F-S 转变的定量预测，通过一种反直觉的方法，该方法侧重于冷却时的局部原子激活事件，而不是弛豫。由于最近邻原子局部协作运动的出现，动态交叉源于由有限原子激活事件控制的笼内原子位置的自调节行为，从而产生无序到有序的转变。此外，还发现了熵在这种异常中的主导作用，并发现了参与激活事件的构型熵的交叉与F-S转变发生之间的对应关系。我们的工作意味着原子激活事件反映的原子能量涨落特征与无序系统的复杂动态行为有着密切的联系。
As a common but critical dynamic crossover in glass-forming liquids (GFLs), the discovery of fragile-to-strong (F-S) transition promises a novel route for understanding supercooled liquid and glass transition. The present work, for the first time, successfully realizes the quantitative prediction of the F-S transition in nine metallic glass-forming liquids, by a counter-intuitive approach that focuses on local atomic activation events, rather than relaxation, upon cooling. The dynamic crossover originates from a disorder-to-order transition by self-regulating behavior of atomic position within a cage controlled by finite atomic activation events, due to the appearance of local cooperative motion of nearest neighborhood atoms. Moreover, the dominant role of entropy in this anomaly has been discovered, and the correspondence between the crossover of configuration entropy involved in activation events and the occurrence of F-S transition has been found. Our work implies that the feature of atomic energy fluctuations reflected by atomic activation events has a close linkage to complex dynamic behaviors of disordered systems.