arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 2201.01208cond-mat.dis-nncond-mat.stat-mech
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玻璃中势垒驱动激活和熵驱动激活之间的竞争

Competition between Barrier- and Entropy-Driven Activation in Glasses

Matthew R. Carbone, Marco Baity-Jesi

摘要:

在简化模型的玻璃,我们澄清存在两种不同的激活动力学,这两种共存,其中一个占主导地位。一种是通常用于描述激活的能垒跳跃,另一种我们称之为熵激活,由缺乏方便的方向驱动。当熵激活占主导地位时,能垒的高度不再是描述系统减速的决定性因素。在我们的分析中,一种机制对另一种机制的主导作用取决于态密度和温度的形状。我们还发现,在低温下的相变之间的两种激活可以发生。我们的框架可以用来协调的便利化和热力学图片的玻璃减速。

英文摘要:

In simplified models of glasses we clarify the existence of two different kinds of activated dynamics, which coexist, with one of the two dominating over the other. One is the energy barrier hopping that is typically used to picture activation, and the other one, which we call entropic activation, is driven by the scarcity of convenient directions. When entropic activation dominates, the height of the energy barriers is no longer the decisive to describe the system's slowdown. In our analysis, dominance of one mechanism over the other depends on the shape of the density of states and temperature. We also find that at low temperatures a phase transition between the two kinds of activation can occur. Our framework can be used to harmonize the facilitation and thermodynamic pictures of the slowdown of glasses.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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