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arXiv · 1012.2434

Gigantic Maximum of Nanoscale Noncontact Friction

Kohta Saitoh·Kenichi Hayashi·Yoshiyuki Shibayama·Keiya Shirahama
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Abstract

We report measurements of noncontact friction between surfaces of NbSe$_{2}$ and SrTiO$_{3}$, and a sharp Pt-Ir tip that is oscillated laterally by a quartz tuning fork cantilever. At 4.2 K, the friction coefficients on both the metallic and insulating materials show a giant maximum at the tip-surface distance of several nanometers. The maximum is strongly correlated with an increase in the spring constant of the cantilever. These features can be understood phenomenologically by a distance-dependent relaxation mechanism with distributed time scales.

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Kohta Saitoh, Kenichi Hayashi, Yoshiyuki Shibayama, Keiya Shirahama. 2010-12-11. Gigantic Maximum of Nanoscale Noncontact Friction. https://doi.org/10.1103/physrevlett.105.236103

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