Antiferromagnetic criticality at a heavy-fermion quantum phase transition

Abstract

The interpretation of the magnetic phase diagrams of strongly correlated electron systems remains controversial. In particular, the physics of quantum phase transitions, which occur at zero temperature, is still enigmatic. Heavy-fermion compounds aretextbook examples of quantum criticality, as doping, or the application of pressure or a magnetic field can lead to a quantum phase transition between a magnetically ordered state and a paramagnetic regime. A central question concerns the microscopic nature of the critical quantum fluctuations. Are they antiferromagnetic or of local origin? Here we demonstrate, using inelastic neutron scattering experiments, that the quantum phase transition in the heavy-fermion system Ce1-xLaxRu2Si2 is controlled by fluctuations of the antiferromagnetic order parameter. At least for this heavy-fermion family, the Hertz-Millis-Moriya spin fluctuation approach seems to be a sound basis for describing the quantum antiferromagnetic-paramagnetic instability.

15 pages, 4 figures

References in corpus (8)

• Fermi-liquid instabilities at magnetic quantum phase transitions
• Quantum Criticality in Heavy Fermion Metals
• Quantum criticality
• Quantum magnetism and criticality
• Anomalous scaling behavior of the dynamical spin susceptibility of Ce${}_{0.925}$La${}_{0.075}$Ru${}_2$Si${}_2$
• Spin Fluctuation in Heavy Fermion CeRu_2Si_2
• Artificial scaling laws of the dynamical magnetic susceptibility in heavy-fermion systems
• Low energy spin fluctuations in the heavy fermion compound Ce${}_{0.925}$La${}_{0.075}$Ru${}_2$Si${}_2$

Cited by in corpus (8)

• Heavy Fermions and Quantum Phase Transitions
• Pressure dependence of superconducting critical temperature and upper critical field of 2H-NbS2
• Heavy fermions in high magnetic field
• Fermi surface topology of the two-dimensional Kondo lattice model: a dynamical cluster approximation approach
• High-field moment polarization in the ferromagnetic superconductor UCoGe
• High-field metamagnetism in the antiferromagnet CeRh${}_2$Si${}_2$
• Magnetic Polarization and Fermi Surface Instability: Case of YbRh2Si2
• Field-induced quantum fluctuations in the heavy fermion superconductor CeCu2Ge2