
Depinning dynamics of driven colloids with random pinning: a numerical study
Chen JiangXing, Feng ChunMu, Wang YouMei, Cao YiGang, Jiao ZhengKuan
Chin. Phys. B, 2004, 13 (5):
778782.
DOI: 10.1088/10091963/13/5/035
Using Langevin simulations, we have investigated numerically the depinning dynamics of driven twodimensional colloids subject to the randomly distributed pointlike pinning centres. With increasing strength of pinning, we find a crossover from elastic to plastic depinnings, accompanied by an order to disorder transition of state and a substantial increase in the depinning force. In the elastic regime, no peaks are found in the differential curves of the velocity－force dependence (VFD) and the transverse motion is almost none. In addition, the scaling relationship between velocity and force is found to be valid above depinning. However, when one enters the plastic regime, a peak appears in the differential curves of VFD and transverse diffusion occurs above depinning. Furthermore, history dependence is found in the plastic regime.
