Nuclear Magnetic Resonance Studies of YTTRIUM(1-X) Uranium(x) PALLADIUM(3)

Host ^{89}Y nuclear magnetic resonance (NMR) experiments on the Kondo alloy system Y_{1-x}U _{x}Pd _3 are reported. NMR frequency shifts and linewidths for this system have been measured as a function of temperature and uranium concentration, x, for x = 0, 0.05, 0.1, and 0.2. The linewidths are large in all of the samples studied, and NMR satellite structure is partially resolvable in the x = 0.05 material. These results indicate the existence of a spatially oscillatory polarization of the conduction electron spin polarization. The temperature dependence of the shape of the ^{89 }Y line in the x = 0.2 material, in which NMR satellites are not separately resolvable, suggests that the conduction electron polarization caused by the uranium impurities is modified by Kondo scattering on a distance scale comparable to the typical uranium spacing. The conventional Kondo coherence length for this material is orders of magnitude larger than the uranium ion spacing and thus does not account for the Kondo scattering indicated by the NMR results, indicating that the ground state of Y_{ 1-x}U_{x}Pd_3 is qualitatively different from the conventional Kondo ground state.