Zheng Guang-Ping, Li Mo
Department of Materials Science and Engineering, The Johns Hopkins University, 3400 North Charles Street, Baltimore, Maryland 21218, USA.
Phys Rev E Stat Nonlin Soft Matter Phys. 2002 Sep;66(3 Pt 2A):036108. doi: 10.1103/PhysRevE.66.036108. Epub 2002 Sep 10.
Dynamic scaling for driven disordered systems is investigated in some disordered Ising models. Using Monte Carlo simulation, we find that avalanches in both random-field and random-bond Ising models follow dynamic power-law scaling in short times, and the scaling relations are universal for the systems studied. The probability distribution of the dynamic scaling exponent theta is found to have two peaks centered at theta(1) and theta(2). The short-time dynamic exponent theta(1) is invariant and universal for all avalanches while the exponent theta(2) depends on the strength of disorder. The analytical result for the early stage evolution of breakdown process in the random-field Ising model is obtained using mean-field approximation. Short-time dynamic scaling is also confirmed.
在一些无序伊辛模型中研究了驱动无序系统的动态标度。通过蒙特卡罗模拟，我们发现随机场和随机键伊辛模型中的雪崩在短时间内都遵循动态幂律标度，并且对于所研究的系统，标度关系是通用的。发现动态标度指数θ的概率分布有两个以θ(1)和θ(2)为中心的峰值。短时间动态指数θ(1)对于所有雪崩都是不变且通用的，而指数θ(2)取决于无序强度。使用平均场近似得到了随机场伊辛模型中击穿过程早期演化的解析结果。短时间动态标度也得到了证实。
