Heavy Fermions and Quantum Phase Transitions

TLDR

Quantum phase transitions, driven by competing interactions, have been identified in many heavy‑fermion antiferromagnets, revealing new quantum critical points, exotic phases, and insights into their electronic, magnetic, and superconducting behavior. The authors review recent developments, discuss open issues, and propose future research directions in heavy‑fermion quantum criticality. The paper conducts a comprehensive review of recent progress, identifies unresolved questions, and suggests future research avenues.

Abstract

Quantum phase transitions arise in many-body systems because of competing interactions that promote rivaling ground states. Recent years have seen the identification of continuous quantum phase transitions, or quantum critical points, in a host of antiferromagnetic heavy-fermion compounds. Studies of the interplay between the various effects have revealed new classes of quantum critical points and are uncovering a plethora of new quantum phases. At the same time, quantum criticality has provided fresh insights into the electronic, magnetic, and superconducting properties of the heavy-fermion metals. We review these developments, discuss the open issues, and outline some directions for future research.