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arXiv 0802.4346cond-mat.dis-nn
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具有软势的玻璃形成系统中的遍历性和慢化:无温度奇异性

Ergodicity and Slowing Down in Glass-Forming Systems with Soft Potentials: No Finite-Temperature Singularities

Jean-Pierre Eckmann, Itamar Procaccia

摘要:

本文的目的是讨论一些基本概念,一般的玻璃形成系统组成的粒子通过软势相互作用。排除明确的硬核相互作用,我们讨论了所谓的“玻璃化转变”,其中形成过冷的非晶态,伴随着一个壮观的减缓松弛平衡,当温度在一个相对较小的时间间隔内变化。利用具有不同相互作用长度尺度的N粒子的50-50二元液体的经典例子,我们表明:(i)系统在所有温度下保持遍历性。(ii)可以计算拓扑上不同的构型的数量,其与温度无关,并且是N的指数。(iii)相空间中的任何两个配置可以连接使用的基本移动的数量是多项式有界的N,表明配置的图形具有“小世界”的属性。(iv)系统的熵可以在任何温度(或能量)下估计,并且在任何正温度下都不存在Kauzmann危机。(v)解释了弛豫时间的超阿氏温度依赖性的机制,将其连接到玻璃化转变时的熵压缩。(vi)在任何有限温度T>0时都不存在Vogel-Fulcher临界点

英文摘要:

The aim of this paper is to discuss some basic notions regarding generic glass forming systems composed of particles interacting via soft potentials. Excluding explicitly hard-core interaction we discuss the so called `glass transition' in which super-cooled amorphous state is formed, accompanied with a spectacular slowing down of relaxation to equilibrium, when the temperature is changed over a relatively small interval. Using the classical example of a 50-50 binary liquid of N particles with different interaction length-scales we show that (i) the system remains ergodic at all temperatures. (ii) the number of topologically distinct configurations can be computed, is temperature independent, and is exponential in N. (iii) Any two configurations in phase space can be connected using elementary moves whose number is polynomially bounded in N, showing that the graph of configurations has the `small world' property. (iv) The entropy of the system can be estimated at any temperature (or energy), and there is no Kauzmann crisis at any positive temperature. (v) The mechanism for the super-Arrhenius temperature dependence of the relaxation time is explained, connecting it to an entropic squeeze at the glass transition. (vi) There is no Vogel-Fulcher crisis at any finite temperature T>0

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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