Towards the Ideal Nano-Friction Experiment

The invention of the Atomic Force Microscope (AFM) has opened the way to the investigation of the fundamental aspects of friction for extremely small contacts, with characteristic length scales into the (sub)nanometer regime, both perpendicular and parallel to the plane of contact (Bhushan et al., 1995). By putting the AFM in ultrahigh vacuum (UHV) and preparing atomically clean surfaces and AFM-tips, one can carry out model experiments on atomic-scale contact formation and friction either in the complete absence of intervening lubricants or with highly idealized model lubricant monolayers.