Experimental aspects of measuring dissipation on atomic scale using large-amplitude dynamic force microscopy are discussed. Dissipation versus distance curves reveal that long- and short-range forces contribute to the dissipation. The decay length of short-range contributions is found to be close to that of the tunneling current. The dependence of dissipation on the bias voltage and on the oscillation amplitude is presented. Atomic-scale lateral variations of dissipation are discussed, and the role of the atomic constitution of the tip for quantitative results is pointed out.

• Received 7 June 2000

DOI:https://doi.org/10.1103/PhysRevB.62.13674