13 C Nuclear Relaxation and Normal-State Properties of K 3 C 60 under Pressure

We report the pressure and temperature dependences of 13C nuclear spin-lattice relaxation time T1 in the normal state of K3C60. From the 1/T1T temperature and pressure profiles, a Fermi-liquid theory is used to investigate the variation of the density of states and the amplitude of electron-electron interaction. Finally the results obtained are shown to support a pairing mechanism for superconductivity that would involve high-frequency modes.