Role of f electrons in rare-earth and uranium intermetallics-An alternative look at heavy-fermion phenomena

TL;DR

This paper offers an alternative perspective on heavy-fermion phenomena in rare-earth and uranium intermetallics by emphasizing the role of f electrons and their contribution to low-temperature properties.

Contribution

It proposes a new interpretation of heavy-fermion behavior focusing on the removal of Kramers degeneracy of f electronic ground states.

Findings

Localized f electrons significantly influence low-temperature specific heat.

Heavy-fermion behavior linked to Kramers degeneracy removal.

Electronic subsystems explain magnetic and electronic properties.

Abstract

The understanding of magnetic and electronic properties of rare-earth intermetallics is summarized. The properties of NdNi5 or ErNi5 are understood by considering a few electronic subsystems like the f electronic subsystem and the conduction-electron subsystem. The localized f electrons can give a substantial contribution to the low temperature specific heat with the entropy of R ln2 in case of Kramers ions. In this view the heavy-fermion behaviour is related with the removal of the Kramers degeneracy of the ground state of the f electronic subsystem.