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Quantum phase transitions in holographic models of magnetism and superconductors
We study a holographic model realizing an "antiferromagnetic" phase in which a global SU(2) symmetry representing spin is broken down to a U(1) by the presence of a finite electric charge density.
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
Universally diverging Grüneisen parameter and the magnetocaloric effect close to quantum critical points.
For a magnetic-field driven transition, similar relations hold for the magnetocaloric effect (1/T) partial differential T/ partial differential H|(S) and the corrections to scaling are determined.
Locally critical quantum phase transitions in strongly correlated metals
The theoretical finding of a locally critical quantum phase transition in a model of heavy fermions is reported, and local criticality is proposed to be a phenomenon of general relevance to strongly correlated metals.
Orbital-selective Mott phase in multiorbital models for alkaline iron selenides K1-xFe2-ySe2.
  • R. Yu, Q. Si
  • Materials Science, Physics
    Physical review letters
  • 28 August 2012
The orbital-selective Mott phase provides a natural link between the superconducting K(1-x)Fe(2-y)Se(2) and its Mott-insulating parent compound and provides a unified framework to understand the interplay between the strength of the vacancy order and carrier doping.
Fermi surface reconstruction and multiple quantum phase transitions in the antiferromagnet CeRhIn5
Measurements of heat capacity and de Haas–van Alphen oscillations at low temperatures across a field-induced antiferromagnetic QCP in the heavy-fermion metal CeRhIn5 demonstrate that at least two distinct classes of QCP are observable in CeRh in a significant step toward the derivation of a universal phase diagram for QCPs.
TOPICAL REVIEW: How do Fermi liquids get heavy and die?
We discuss non-Fermi liquid and quantum critical behaviour in heavy-fermion materials, focusing on the mechanism by which the electron mass appears to diverge at the quantum critical point. We ask
Quantum criticality and global phase diagram of magnetic heavy fermions
  • Q. Si
  • Physics
  • 1 December 2009
Quantum criticality describes the collective fluctuations of matter undergoing a second‐order phase transition at zero temperature. It is being discussed in a number of strongly correlated electron
Local fluctuations in quantum critical metals
We show that spatially local, yet low-energy, fluctuations can play an essential role in the physics of strongly correlated electron systems tuned to a quantum critical point. A detailed microscopic
High Temperature Superconductivity in Iron Pnictides and Chalcogenides
Superconductivity develops in metals upon the formation of a coherent macroscopic quantum state of electron pairs. Iron pnictides and chalcogenides are materials that have high superconducting