Caging and mosaic length scales in plaquette spin models of glasses
Caging and mosaic length scales in plaquette spin models of glasses
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DOI：
10.1063/1.2075067
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发表时间：
2005-10-22
影响因子：
4.4
通讯作者：
Garrahan, JP
中科院分区：
文献类型：
--
作者：
Jack, RL;Garrahan, JP
我们考虑两个系统的伊辛自旋与元格相互作用。它们是具有作为动力学约束系统的双重表示的眼镜的简单模型。这些模型允许明确的分析使用马赛克，或熵液滴，方法的随机一级转变理论的玻璃化转变。我们发现，这些系统的低温状态类似于玻璃马赛克状态，尽管事实上，激发是本地化的，并且没有静态奇点。通过有限尺寸热力学，我们研究了一个广义的笼子效应，即系统是冻结在短的长度尺度，但在更大的长度尺度自由。我们发现，从静态得到的冻结长度尺度与动态相关性相吻合，正如预期的马赛克视图。简单的成核参数的马赛克的方法，但是，不给出正确的冻结长度和弛豫时间之间的关系，因为它们不捕获弛豫的过渡态。我们讨论了这些结果之间的连接的马赛克和玻璃成型机的动态促进意见。(c)2005年美国物理学会。
We consider two systems of Ising spins with plaquette interactions. They are simple models of glasses which have dual representations as kinetically constrained systems. These models allow an explicit analysis using the mosaic, or entropic droplet, approach of the random first-order transition theory of the glass transition. We show that the low-temperature states of these systems resemble glassy mosaic states, despite the fact that excitations are localized and that there are no static singularities. By means of finite-size thermodynamics we study a generalized caging effect whereby the system is frozen on short length scales, but free at larger length scales. We find that the freezing length scales obtained from statics coincide with those relevant to dynamic correlations, as expected in the mosaic view. The simple nucleation arguments of the mosaic approach, however, do not give the correct relation between freezing lengths and relaxation times, as they do not capture the transition states for relaxation. We discuss how these results make a connection between the mosaic and the dynamic facilitation views of glass formers. (c) 2005 American Institute of Physics.