The Puzzling Collapse of Electronic Sliding Friction on a Superconductor Surface

TL;DR

This paper investigates the sudden decrease in electronic sliding friction observed on a superconducting lead surface, exploring potential mechanisms and implications for electronic friction theories.

Contribution

It provides a discussion on possible mechanisms behind the abrupt friction drop and its relevance to electronic friction in superconducting materials.

Findings

Friction force drops by a factor of ~2 below the superconducting transition.

Discussion of mechanisms for the abrupt friction change.

Relevance to electronic friction in superconductors.

Abstract

In a recent paper [Phys. Rev. Lett. 80 (1998) 1690], Krim and coworkers have observed that the friction force, acting on a thin physisorbed layer of N_2 sliding on a lead film, abruptly decreases by a factor of ~2 when the lead film is cooled below its superconductivity transition temperature. We discuss the possible mechanisms for the abruptness of the sliding friction drop, and also discuss the relevance of these results to the problem of electronic friction.