Fluctuations and jump dynamics in atomic friction experiments

Atomic stick-slip processes have been studied in detail by means of friction force microscopy with high spatial and temporal resolution. The influence of the tip-sample contact on the thermal fluctuations of the force sensor and on the dynamics of the stick-slip process are characterized. Results are compared with simulations based on an extended Tomlinson model including thermal fluctuations. A correlation between the duration of the atomic slip event and the atomic structure of the contact is established.