LiV2O4: A Heavy Fermion Transition Metal Oxide

A crossover with decreasing temperature $T$ from localized moment magnetism to heavy Fermi liquid behavior is reported for the metallic compound ${\mathrm{LiV}}_2{\mathrm{O}}_4$ with the fcc normal-spinel structure. At $T=1\mathrm{}\mathrm{K}$, the electronic heat capacity coefficient $\gamma \approx 0.42\mathrm{J}/\mathrm{mol}{\mathrm{K}}^2$ is exceptionally large for a transition metal compound, the Wilson ratio $\approx 1.7$, and the Korringa ratio $\approx 0.7$. Our sample with the lowest level of paramagnetic defects showed no static magnetic order above 0.02 K. Superconductivity was not observed above 0.01 K.