Fermi-liquid instabilities at magnetic quantum phase transitions

Authors:
  • HLHilbert V. Löhneysen
    Hilbert V. Löhneysen
  • ARAchim Rosch
    Achim Rosch
  • MVMatthias Vojta
    Matthias Vojta
  • PWPeter Wölfle
    Peter Wölfle
Preprint
Publisher website
Google Scholar
Abstract
This review discusses instabilities of the Fermi-liquid state of conduction electrons in metals with particular emphasis on magnetic quantum critical points. We present both the existing theoretical concepts and experimental data on selected materials, with the aim of assessing the validity of presently available theory. After briefly recalling the fundamentals of Fermi-liquid theory, we describe the local Fermi-liquid state in quantum impurity models and their lattice versions and discuss how it may break down, leading to particular quantum phase transitions. Next, the scaling concepts applicable to quantum phase transitions are presented. The Hertz-Millis-Moriya theory of quantum phase transitions is described in detail. The breakdown of the latter is analyzed in several examples. In the final part experimental data on heavy-fermion materials and transition-metal alloys are reviewed and confronted with existing theory.