Fig. 3

Examples of locking and unlocking. a A schematic view showing how the particle lands on the speed-locking region \(\lambda_{1}\) of wavy graphene surface where the initial particle speed is \(v_{0} = 2175\,{{\text{m}} \mathord{\left/ {\vphantom {{\text{m}} {\text{s}}}} \right. \kern-\nulldelimiterspace} {\text{s}}}\); b a schematic view showing how the particle lands on the speed unlocking region \(\lambda_{2}\) of the wavy graphene surface; c the trajectories of particles by both MD simulation and theory, the trajectory of a particle on flat graphene is also plotted for comparison; d the time evolution of particle velocity by Eq. (6); e the trajectories of particle by both MD simulation and theory; f the time evolution of particle velocity by Eq. (6)