PENETRATION DEPTH AND COHERENCE LENGTH IN SUPERCONDUCTING FULLERENE Rb3C60

Abstract

The penetration depth λ and the coherence length ξ in Rb 3 C 60 fullerene are determined by means of magnetic measurements in fields up to 50 kOe. For the Ginzburg-Landau coherence length the estimate ξ GL (0)=23 Å is obtained, while the magnitude of λ GL (0) extracted from the high-field data turns out to lie between 1200 and 1400 Å, with the upper value being more likely. Non-superconducting diamagnetic susceptibility is also measured and found to be equal to −(0.60±0.02)×10−5 which is an order of magnitude higher than that of undoped fullerene.