Fullerene Superconductors
Abstract
The electrical, magnetic and optical properties of the fullerene superconductors K3C60 and Rb3C60 have been investigated. The room temperature microwave resistivity at 60 GHz of pressed powder samples of K3C60 is approximately 5m (ohms) cm. The resistivity drops by almost one order of magnitude on cooling to 20K, indicative of metallic behavior, before the samples superconduct at T (sub) c = 19.3K. Optical reflectivity spectra are consistent with metallic materials. An extrapolation of the frequency dependence of conductivity leads to d.c. conductivities of 1.3 x 10 (exp 3) (ohm)-l and 1.2 x 10 (exp 3) (ohm)-l for K3C60 and Rb3C60, respectively. The gap values A of 24 / cm for K3C60 and 30 /cm for Rb3C60 are consistent with weak-coupling and a BCS singlet ground state. Upper critical fields of 28-30 Tesla for K3C60 and 38-55 Tesla for Rb3C60 have been measured. The lower values are from static magnetic experiments, while the upper values used pulsed magnets.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 17, 1993
- Accession Number
- ADA266749
Entities
People
- Richard Kaner
Organizations
- University of California, Los Angeles