Phase transitions of hard disks in external periodic potentials: a Monte Carlo study.
Phase transitions of hard disks in external periodic potentials: a Monte Carlo study.
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外部周期势下硬盘的相变：蒙特卡罗研究。
DOI：
10.1103/physreve.63.046106
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发表时间：
2000
期刊：
影响因子：
--
通讯作者：
P. Nielaba
中科院分区：
文献类型：
--
作者：
W. Strepp;S. Sengupta;P. Nielaba
利用大量的蒙特卡罗模拟研究了空间周期外势中硬盘系统的冻结和熔化转变的性质。通过对有序参数及其累积量等各种热力学变量进行详细的有限尺寸标度分析，绘制了不同外势密度和幅值下系统的相图。我们在参数空间的一个重要区域上发现了可重入液相的明显迹象。因此，我们的模拟表明，硬盘系统的行为方式类似于已知的电荷稳定胶体，即经历初始冻结，然后随着交叉激光产生的外加调制场的幅度稳步增加而发生重熔转变。对我们数据的详细分析显示了与最近激光诱导熔化的位错解结合理论相一致的几个特征。
The nature of freezing and melting transitions for a system of hard disks in a spatially periodic external potential is studied using extensive Monte Carlo simulations. Detailed finite size scaling analysis of various thermodynamic quantities like the order parameter, its cumulants, etc., are used to map the phase diagram of the system for various values of the density and the amplitude of the external potential. We find clear indication of a reentrant liquid phase over a significant region of the parameter space. Our simulations therefore show that the system of hard disks behaves in a fashion similar to charge-stabilized colloids that are known to undergo an initial freezing, followed by a remelting transition as the amplitude of the imposed, modulating field produced by crossed laser beams is steadily increased. Detailed analysis of our data shows several features consistent with a recent dislocation unbinding theory of laser induced melting.