Magnetic Properties of Superconducting Rb ₃ C ₆₀

Abstract

Magnetic susceptibility, magnetization curves and flux creep of superconducting Rb3C60 with Tc = 27.5 K have been studied. The critical current for Rb3C60 was evaluated to be 4 · 106 A/cm2 at 7 K and 10 kOe, which is considerably higher than for K3C60. The flux creep measurements give the activation energy of U(7 K) ≈ 3.3 · 10-2 eV.