Magnetic Properties of Superconducting Rb3C60

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.