We discuss chemical trends relating to the formation of heavy electron compounds by uranium. © 1987.

The large γ of heavy-electron materials is predominantly a single-ion effect: γ α 1 TK. The most interesting physical effects occur in the low-temperature coherent state of a chemically ordered lattice of these ions. The large-γ state can be strongly quenched by magnetic order, and we argue that this effect is more pronounced for Ce than U materials. We discuss recent work in this light, and address the interesting possibility of heavy-electron materials in which charge fluctuation effects may be important. © 1988.

We have studied the response of heavy-fermion magnets UCd11, U2Zn17 and UAgCu4 to hydrostatic pressures exceeding 17 kbar through temperature-dependent electrical resistance measurements. Results for U2Zn17 and UAgCu4 can be understood in terms of competing Kondo and RKKY interactions. UCd11 exhibits two new phase transitions induced by pressure. © 1986.

We motivate the descriptionof heavy-electron metals in terms ofconcepts from the Kondo problem. These concepts are used to discuss magnetism and superconductivity in heavy-electron systems. Particularattention is given to what weview as the principal outstanding questions in this field and directionsin which the field is developing. This will include consideration of thedifferences between Ce and U heavy-electron compounds as well as the occurrence ofvery small ordered magnetic moments. © The Japan Society of Applied Physics.

The superconducting compounds of uranium exhibit a large range of lattice spacings and of electronic specific heat γ values. Recent work has revealed superconductivity to be more common in such systems than formerly believed. © 1985.

We review the experimental results on heavy-fermion uranium based superconductors and magnets. © 1985.

Superconductivity has been observed in uranium compounds with partly disordered Cu3Au-type crystal structure and interatomic UU distances of more than 4 A. Low-temperature specific-heat experiments reveal no anomalous enhancement of the electronic specific heat thus distinguishing the present materials from the unconventional superconductors UBe13 and UPt3. © 1985 The American Physical Society.

A new class of metals has been found in which the electrons have effective masses orders of magnitude larger than the free-electron mass. Some of these metals are superconducting at low temperatures. This superconductivity seems to be unconventional, with an underlying mechanism different from that in all other known superconductors. © 1986 Nature Publishing Group.