原子尺度下摩擦的失稳和耗散动力学

Instability and dissipation dynamics in atomic scale friction

摘要:

采用 Frenkel-Kontorova 模型和基于双质量双弹簧模型的等效耦合振子模型求解了探针与基底间几种不同耦合类型的能量耗散动力学问题. 发现了纳米尺度下能量耗散失稳现象, 并通过平均耗散功率和粒子相对于质心的位移分析了正弦势和多阱周期性基底势两种情况下的能量耗散特性. 计算结果与最近采用摩擦力显微镜观察的实验结果进行了比较.

Abstract:

Using two different methods, Frenkel-Kontorova (FK) model and equivalent coupled-oscillator model based on two-mass-two-spring model, we solve the dynamics of energy dissipation for several types of coupling between the tip and the substrate. We find the unstable energy dissipation phenomenon on the nanoscale and present a microscopic analysis of properties of energy dissipation via average power dissipated and displacement of the particles relative to the center of mass for sinusoidal potential as well as multiple-well periodic substrate potentials. The results are compared with the observations in recent experiments based on friction force microscope (FFM).