LiV 2 O 4 : 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 LiV{sub 2}O{sub 4} with the fcc normal-spinel structure. At T=1K, the electronic heat capacity coefficient {gamma}{approx}0.42J/molK{sup 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 0.02K. Superconductivity was not observed above 0.01K. {copyright} {ital 1997} {ital The American Physical Society}