119Sn NMR Study of Heavy Fermion Compound U3Ni3Sn4

The 119 Sn Knight shift K and nuclear spin-lattice relaxation time T 1 in a heavy fermion compound U 3 Ni 3 Sn 4 have been measured between 1.5 and 270 K. The K vs the susceptibility plot is linear and yields a hyperfine field of 53.2 kOe/µ B . The nuclear relaxation rate due to U 5f moments (1/ T 1 ) f decreases markedly below about 20 K and is proportional to temperature below about 4 K, where the system is in the Fermi liquid state. The relaxation rate of 5f moments obtained from (1/ T 1 ) f increases linearly with temperature above about 120 K, indicating that the Korringa mechanism is dominant in the fluctuation of localized 5f moments.