The effect of lateral vibrations on transport and friction in nanoscale contacts

We demonstrate that lateral vibrations of a substrate can dramatically increase surface diffusivity and mobility and reduce friction at the nanoscale. In contrast to the enhancement of diffusion and mobility that has a resonance nature, the reduction of friction does not exhibit pronounce resonance features. We find an abrupt dilatancy transition from the state with a small tip-surface separation to the state with a large separation as the vibration frequency increases. Dilatancy is shown to play an essential role in dynamics of a nanometer-size tip which interacts with a vibrating surface. Atomic force microscopy (AFM) experiments are suggested which can test the predicted effects.