Amplitude nanofriction spectroscopy

Atomic scale friction, an indispensable element of nanotechnology, requires a direct access to, under actual growing shear stress, its successive live phases: from static pinning, to depinning and transient evolution, eventually ushering in steady state kinetic friction. Standard tip-based atomic force microscopy generally addresses the steady state, but the prior intermediate steps are much less explored. Here we present an experimental and simulation approach, where an oscillatory shear force of increasing amplitude leads to a one-shot investigation of all these successive aspects. Demonstration with controlled gold nanocontacts sliding on graphite uncovers phenomena that bridge the gap between initial depinning and large speed sliding, of potential relevance for atomic scale time and magnitude dependent rheology.

Automated summary

In this study, an experimental and simulation approach was used to investigate the successive live phases of atomic scale friction by applying an oscillatory shear force with increasing amplitude. The demonstration with controlled gold nanocontacts sliding on graphite revealed phenomena bridging the gap between initial depinning and large speed sliding.