Normal phase of heavy-fermion UPt3

Abstract

A review is presented of the normal-state properties of the heavy-fermion superconductor UPt3 (γ = 422 mJ/K2 molU). At present a large variety of experiments has been performed on good quality single crystals. These studies include specific heat, thermal expansion, susceptibility, electrical resistivity, magnetostriction etc., as well as the application of high-magnetic fields and high pressures. Most of these experiments reveal pronounced anomalies at low temperatures. The thermal properties can be fairly described in a spin-fluctuation model. The magnetic properties are strongly anisotropic. On alloying UPt3 with Pd, additional anomalies, probably of antiferromagnetic nature, are introduced in the material. In spite of a tremendous effort to unravel the intriguing low-temperature properties of UPt3, some of them remain quite puzzling. Fortunately the interest from theoretical site in heavy-fermion compounds in growing. In this respect the application of Fermi-liquid theory to UPt3 is discussed. In addition, recent data on the temperature dependence of the magnetoresistance and on the pressure dependence of the susceptibility, obtained on single-crystalline UPt3 samples, and thermal expansion data on polycrystalline U(Pt,Pd)3 compounds, are presented.