Dramatic Change of the Magnetic Response inLiV2O4: Possible Heavy Fermion to Itinerantd-Metal Transition

Abstract
The magnetic relaxation of the d-metal oxide LiV2O4 has been measured by means of quasielastic neutron scattering. At low temperatures, the observed residual linewidth of 0.5 meV and a square-root temperature dependence of the magnetic relaxation rate are canonical features of heavy-fermion systems. For T>40K the magnetic response changes dramatically and can be characterized as a metal close to ferromagnetic order.