NMR INVESTIGATION OF SUPERCONDUCTIVITY AND KONDO-COHERENCY IN CECU2SI2

In the normal dense Kondo state of CeCu//2Si//2, the nuclear magnetic relaxation rate 1/T//1 of **6**3Cu divided by T, 1/T//1T is almost constant below 2. 5 K with a slight increase near the superconducting transition temperature. Together with the results of other normal Kondo lattice compounds, it is concluded that the temperature dependence of 1/T//1T at low temperatures does not scale to that of the specific heat divided by T, C(T)/T in Kondo lattice compounds in contrast with the case of dilute Kondo impurities. In the superconducting state, 1/T//1T varies as T**2, suggesting the gap zeros along lines, while the reported data of C//s(T)/T show no simple power law dependence. It is claimed that this difference below T//c may be correlated with the difference between 1/T//1T and C(T)/T in the normal dense Kondo state.