Indications of non-Fermi liquid behavior at the metamagnetic transition of UPt3

The specific heat and resistivity of high purity needle crystals and the magnetization of a 300 mg piece of a Czochralski-process single crystal of UPt3 aligned so that B⊥c were measured at 0, 18, 19, 20, 22, and 24 T applied fields between 0.5 and 10 K, where Bmetamag.≈20 T. The data for C/T, ρ, and χ at 18 T and for C/T and ρ at 24 T indicate that there is still Fermi liquid behavior at low temperatures for B≠Bmetamag.. (For B≥21 T, χ displays apparent ferromagnetic behavior.) However, at Bmetamag.C/T is found to be proportional to −log T, or characteristic of non-Fermi liquid (nFl) behavior, over more than a decade in temperature while ρ=ρ0+AT1.2 at 22 T (0.5 K≤T≤3 K) and χ=χ0−aT at 20.5 T (0.5 K≤T≤20 K)—also both characteristic of nFl behavior. This C/T∝−log T behavior is a different nFl temperature dependence than previously found for CeRu2Si2 near its Bmetamag., where C/T was found to decrease linearly with increasing temperature. Thus, although metamagnetism in these, and other, yet to be studied, highly correlated f-electron systems may be a route for attaining long range magnetic interactions that prohibit Fermi-liquid behavior, already the first two systems studied show varying behavior. dHvA data at Bmetamag. for CeRu2Si2 and Shubnikov–de Haas (SdH) data at Bmetamag. for UPt3, and theories thereof, will be compared. The SdH data shed light on the present χ(H) data for UPt3 for B>Bmetamag..