Fast diffusion induced by thermal fluctuation and vibration has been detected at nanoscales. In this paper, the movement of particle on a graphene layer with travelling surface wave is studied by molecular dynamics simulation and theoretical model. It is proved that the particle will keep moving at the wave speed with certain prerequisite conditions, namely speed-locking effect. By expressing van der Waals (vdW) potential between particle and wavy surface as a function of curvatures, the mechanism is clarified based on the puddle of potential in a relative wave-frame coordinate. Two prerequisite conditions are proposed: the initial position of particle should locate in the potential puddle, and the initial kinetic energy cannot drive particle to jump out of the potential puddle. The parametric analysis indicates that the speed-locking region will be affected by wavelength, amplitude and pair potential between particle and wave. With smaller wavelength, larger amplitude and stronger vdW potential, the speed-locking region is larger. This work reveals a new kind of coherent movement for particles on layered material based on the puddle potential theory, which can be an explanation for fast diffusion phenomena at nano scales.

由热波动和振动引起的快速扩散已在纳米级被检测到。本文通过分子动力学模拟和理论模型研究了石墨烯在石墨烯层上随行波的运动。实践证明，在一定的前提条件下，粒子将保持波速运动，即锁速作用。通过将粒子与波浪表面之间的范德华（vdW）电势表示为曲率的函数，基于相对波框坐标中的电势水坑来阐明机理。提出了两个前提条件：粒子的初始位置应位于潜在的水坑中，并且初始动能不能驱动粒子跳出潜在的水坑。参数分析表明，速度锁定区域将受粒子，波与波之间的波长，幅度和对电势的影响。波长越小，振幅越大，vdW电位越强，则速度锁定区域越大。这项工作揭示了一种基于水坑势理论的新型粒子在层状材料上的相干运动，这可以解释纳米级的快速扩散现象。