Abstract
We have employed a quartz crystal microbalance technique to measure the friction associated with sliding of solid nitrogen along a lead surface, above and below the lead's superconducting transition temperature. The friction is observed to drop abruptly at the transition as the substrate enters the superconducting state. The observation signifies a new phenomenon, most likely attributable to electronic contributions to friction. While such contributions have been discussed and debated theoretically for a number of years, they have heretofore not been observed in any direct experimental fashion.
- Received 29 September 1997
DOI:https://doi.org/10.1103/PhysRevLett.80.1690
©1998 American Physical Society
