Luo Liang, Tang Lei-Han
Beijing Computational Science Research Center, Beijing 100094, China.
Department of Physics and Institute of Computational and Theoretical Studies, Hong Kong Baptist University, Hong Kong.
Phys Rev E Stat Nonlin Soft Matter Phys. 2015 Oct;92(4):042137. doi: 10.1103/PhysRevE.92.042137. Epub 2015 Oct 16.
Above two dimensions, diffusion of a particle in a medium with quenched random traps is believed to be well described by the annealed continuous-time random walk. We propose an approximate expression for the first-passage-time (FPT) distribution in a given sample that enables detailed comparison of the two problems. For a system of finite size, the number and spatial arrangement of deep traps yield significant sample-to-sample variations in the FPT statistics. Numerical simulations of a quenched trap model with power-law sojourn times confirm the existence of two characteristic time scales and a non-self-averaging FPT distribution, as predicted by our theory.
在上述两个维度中，粒子在具有淬火随机陷阱的介质中的扩散被认为可以通过退火连续时间随机游走得到很好的描述。我们为给定样本中的首次通过时间（FPT）分布提出了一个近似表达式，该表达式能够对这两个问题进行详细比较。对于有限大小的系统，深陷阱的数量和空间排列会导致FPT统计量在样本之间产生显著变化。具有幂律逗留时间的淬火陷阱模型的数值模拟证实了我们的理论所预测的两个特征时间尺度和非自平均FPT分布的存在。
