Van Hove singularities in the paramagnetic phase of the Hubbard model: a DMFT study

Abstract

Using the dynamical mean-field theory (DMFT) we study the paramagnetic phase of the Hubbard model with the density of states (DOS) corresponding to the three-dimensional cubic lattice and the two-dimensional square lattice, as well as a DOS with inverse square root singularity. We show that the electron correlations rapidly smooth out the square-root van Hove singularities (kinks) in the spectral function for the 3D lattice and that the Mott metal-insulator transition (MIT) as well as the magnetic-field-induced MIT differ only little from the well-known results for the Bethe lattice. The consequences of the logarithmic singularity in the DOS for the 2D lattice are more dramatic. At half filling, the divergence pinned at the Fermi level is not washed out, only its integrated weight decreases as the interaction is increased. While the Mott transition is still of the usual kind, the magnetic-field-induced MIT falls into a different universality class as there is no field-induced localization of quasiparticles. In the case of a power-law singularity in the DOS at the Fermi level, the power-law singularity persists in the presence of interaction, albeit with a different exponent, and the effective impurity model in the DMFT turns out to be a pseudo-gap Anderson impurity model with a hybridization function which vanishes at the Fermi level. The system is then a generalized Fermi liquid. At finite doping, regular Fermi liquid behavior is recovered.

7 pages, 9 figures

References in corpus (12)

• The numerical renormalization group method for quantum impurity systems
• Sum-rule Conserving Spectral Functions from the Numerical Renormalization Group
• Singular Fermi Liquids
• Energy resolution and discretization artefacts in the numerical renormalization group
• Robustness of the van Hove scenario for high-Tc superconductors
• Electron spectra close to a metal-to-insulator transition
• Dynamical Mean Field Study of the Two-Dimensional Disordered Hubbard Model
• Field dependent quasiparticles in the infinite dimensional Hubbard model
• Convergence acceleration and stabilization for dynamical-mean-field-theory calculations
• Field dependent quasiparticles in models of strongly correlated electrons
• A fractional-spin phase in the power-law Kondo model
• Quasiparticle properties of strongly correlated electron systems with itinerant metamagnetic behavior

Cited by in corpus (24)

• The coherence-incoherence crossover and the mass-renormalization puzzles in Sr2RuO4
• The Kondo effect in the presence of the Rashba spin-orbit interaction
• Dynamical Mean Field Theory of Moiré Bilayer Transition Metal Dichalcogenides: Phase Diagram, Resistivity, and Quantum Criticality
• Spectral properties of the three-dimensional Hubbard model
• Spectral properties of Dirac billiards at the van Hove singularities
• Non-Fermi liquid signatures in the Hubbard Model due to van Hove singularities
• Doublon-holon binding, Mott transition, and fractionalized antiferromagnet in the Hubbard model
• Role of the van Hove Singularity in the Quantum Criticality of the Hubbard Model
• Mott quantum criticality in the one-band Hubbard model: Dynamical mean-field theory, power-law spectra, and scaling
• Temperature and doping induced instabilities of the repulsive Hubbard model on Lieb lattice
• Spin-orbit and anisotropic strain effects on the electronic correlations of Sr${}_2$RuO${}_4$
• A local theory for Mott-Anderson localization
• Repulsive vs. attractive Hubbard model: transport properties and spin-lattice relaxation rate
• On the nature of the Mott transition in multiorbital systems
• Kondo effect at low electron density and high particle-hole asymmetry in 1D, 2D, and 3D
• Nonadiabatic Time-Dependent Spin-Density Functional Theory for strongly correlated systems
• Mott metal-insulator transition from steady-state density functional theory
• Spin-1 two-impurity Kondo problem on a lattice
• Dynamic charge Kondo effect and a slave fermion approach to the Mott transition
• Electric control of two-dimensional Van Hove singularity in oxide ultra-thin films
• Charge Collective Modes in Correlated Electron Systems: Plasmons Beyond the Random Phase Approximation
• Quantum impurity with 2/3 local moment in 1D quantum wires: an NRG study
• Dynamics of magnetic collective modes in the square and triangular lattice Mott insulators at finite temperature
• Hund's metallicity enhanced by van Hove singularity in cubic perovskite systems