Long range order and two-fluid behavior in heavy electron materials

Abstract

The heavy electron Kondo liquid is an emergent state of condensed matter that displays universal behavior independent of material details. Properties of the heavy electron liquid are best probed by NMR Knight shift measurements, which provide a direct measure of the behavior of the heavy electron liquid that emerges below the Kondo lattice coherence temperature as the lattice of local moments hybridizes with the background conduction electrons. Because the transfer of spectral weight between the localized and itinerant electronic degrees of freedom is gradual, the Kondo liquid typically coexists with the local moment component until the material orders at low temperatures. The two-fluid formula captures this behavior in a broad range of materials in the paramagnetic state. In order to investigate two-fluid behavior and the onset and physical origin of different long range ordered ground states in heavy electron materials, we have extended Knight shift measurements to URu${}_2$Si${}_2$, CeIrIn${}_5$ and CeRhIn${}_5$. In CeRhIn${}_5$ we find that the antiferromagnetic order is preceded by a relocalization of the Kondo liquid, providing independent evidence for a local moment origin of antiferromagnetism. In URu${}_2$Si${}_2$ the hidden order is shown to emerge directly from the Kondo liquid and so is not associated with local moment physics. Our results imply that the nature of the ground state is strongly coupled with the hybridization in the Kondo lattice in agreement with phase diagram proposed by Yang and Pines.

9 pages, 13 figures

References in corpus (8)

• Fermi-liquid instabilities at magnetic quantum phase transitions
• Quantum criticality
• Gapped itinerant spin excitations account for missing entropy in the hidden order state of URu${}_2$Si${}_2$
• Universal Behavior in Heavy Electron Materials
• Nuclear magnetic resonance in the heavy fermion superconductors
• Electronic Duality in Strongly Correlated Matter
• Fermi surface and antiferromagnetism in the Kondo lattice: an asymptotically exact solution in d>1 Dimensions
• Magnetic excitations in Kondo liquid: Superconductivity and Hidden Magnetic Quantum Critical Fluctuations

Cited by in corpus (5)

• Crossover in the magnetic response of single-crystalline Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$ and Lifshitz critical point evidenced by Hall effect measurements
• Universal Knight shift anomaly in the Periodic Anderson model
• The Emergence of Superconductivity in Heavy Electron Materials
• Quantum critical behavior in heavy electron materials
• Anomalous Hall effect in heavy electron materials