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Quantum criticality in heavy-fermion metals
Quantum criticality describes the collective fluctuations of matter undergoing a second-order phase transition at zero temperature. Heavy-fermion metals have in recent years emerged as prototypical
Antiferromagnetic Mott insulating state in single crystals of the hexagonal lattice material Na2IrO3
We have synthesized single crystals of Na_2IrO_3 and studied their structure, transport, magnetic, and thermal properties using powder x-ray diffraction (PXRD), electrical resistivity, isothermal
YbRh2Si2: Pronounced Non-Fermi-Liquid Effects above a Low-Lying Magnetic Phase Transition
We report the first observation of non-Fermi-liquid (NFL) effects in a clean Yb compound at ambient pressure and zero magnetic field. The electrical resistivity and the specific-heat coefficient of
The break-up of heavy electrons at a quantum critical point
It is inferred that all ballistic motion of electrons vanishes at a QCP, forming a new class of conductor in which individual electrons decay into collective current-carrying motions of the electron fluid.
Models and materials for generalized Kitaev magnetism.
The mechanism proposed by Jackeli and Khaliullin to identify Kitaev materials based on spin-orbital dependent bond interactions is analyzed and a comprehensive overview of its implications in real materials is provided.
Spin waves and revised crystal structure of honeycomb iridate Na2IrO3.
Combining single-crystal diffraction and density functional calculations, a revised crystal structure model with significant departures from the ideal 90° Ir-O-Ir bonds required for dominant Kitaev exchange is proposed.
Na2IrO3 as a novel relativistic Mott insulator with a 340-meV gap.
Na2IrO3 is established as a novel type of Mott-like correlated insulator in which Coulomb and relativistic effects have to be treated on an equal footing.
High-field phase diagram of the heavy-fermion metal YbRh2Si2
The tetragonal heavy-fermion (HF) metal YbRh2Si2 (Kondo temperature TK≈ 25 K) exhibits a magnetic field-induced quantum critical point related to the suppression of very weak antiferromagnetic (AF)
Hall-effect evolution across a heavy-fermion quantum critical point
Measurements of the low-temperature Hall coefficient (RH)—a measure of the Fermi surface volume—in the heavy-fermion metal YbRh2Si2 upon field-tuning it from an antiferromagnetic to a paramagnetic state are reported.
Magnetic-field induced quantum critical point in YbRh(2)Si(2).
Low-temperature calorimetric, magnetic, and resistivity measurements on the antiferromagnetic heavy-fermion metal YbRh( 2)Si(2) ( T(N)=70 mK) as a function of magnetic field B suggest singular scattering at the whole Fermi surface and a divergence of the heavy quasiparticle mass.