Anisotropic two-orbital Hubbard model: single-site versus cluster dynamical mean-field theory
arXiv:1106.5255 · doi:10.1002/andp.201100021
Abstract
The anisotropic two-orbital Hubbard model with different bandwidths and degrees of frustration in each orbital is investigated in the framework of both single-site dynamical mean-field theory (DMFT) as well as its cluster extension (DCA) for clusters up to four sites combined with a continuous-time quantum Monte Carlo algorithm. This model shows a rich phase diagram which includes the appearance of orbital selective phase transitions, non-Fermi liquid behavior as well as antiferromagnetic metallic states. We discuss the advantages and drawbacks of employing the single-site DMFT with respect to DCA and the consequences for the physical picture obtained out of these calculations. Finally, we argue that such a minimal model may be of relevance to understand the nature of the antiferromagnetic metallic state in the iron-pnictide superconductors as well as the origin of the small staggered magnetization observed in these systems.
7 pages, 4 figures, and accepted in Annalen der Physik
References in corpus (37)
- Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
- Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsOF}
- Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides
- Origin of the ~150 K Anomaly in LaOFeAs; Competing Antiferromagnetic Superexchange Interactions, Frustration, and Structural Phase Transition
- Correlated electronic structure of LaOFeAs
- Coherence-incoherence crossover in the normal state of iron-oxypnictides and importance of the Hund's rule coupling
- Hybridization expansion impurity solver: General formulation and application to Kondo lattice and two-orbital models
- The challenge of unravelling magnetic properties in LaFeAsO
- Cluster Dynamical Mean Field Theory of the Mott Transition
- Comparison of Ab initio Low-Energy Models for LaFePO, LaFeAsO, BaFe2As2, LiFeAs, FeSe and FeTe: Electron Correlation and Covalency
- Orbital-Selective Mott transition out of band degeneracy lifting
- Continuous-time auxiliary field Monte Carlo for quantum impurity models
- Orbital selective Mott transition in multi-band systems: slave-spin representation and dynamical mean-field theory
- High-spin to low-spin and orbital polarization transitions in multiorbital Mott systems
- Strongly Correlated Superconductivity: a plaquette Dynamical mean field theory study
- Fermi-liquid, non-Fermi-liquid, and Mott phases in iron pnictides and cuprates
- Anisotropy, Itineracy, and Magnetic Frustration in High-Tc Iron Pnictides
- Diagrammatic Determinantal methods: projective schemes and applications to the Hubbard-Holstein model
- Local Order and the gapped phase of the Hubbard model: a plaquette dynamical mean field investigation
- Antiferromagnetism and the gap of a Mott insulator: Results from analytic continuation of the self-energy
- Pseudogap and Mott Transition Studied by Cellular Dynamical Mean Field Theory
- Classification of the electronic correlation strength in the Fe-pnictides: The case of the parent compound BaFe2As2
- Orbital-selective Mott-Hubbard transition in the two-band Hubbard model
- Normal State Correlated Electronic Structure of Iron Pnictides
- Orbital-selective Mott transitions in the anisotropic two-band Hubbard model at finite temperatures
- Low magnetization and anisotropy in the antiferromagnetic state of undoped iron pnictides
- Microscopic origin of pressure-induced phase transitions in iron-pnictide superconductors: an {ab initio} molecular-dynamics study
- Study of the Hubbard model on the triangular lattice using dynamical cluster approximation and dual fermion methods
- Frustrated local moment models for Fe-pnictide magnetism
- Proximity of LaOFeAs to a magnetic instability
- Itinerant Nature of Magnetism in Iron Pnictides: A first principles study
- Analysis of spin density wave conductivity spectra of iron pnictides in the framework of density functional theory
- Magnetic Properties of Ab initio Model for Iron-Based Superconductors LaFeAsO
- Dynamical cluster approximation study of the anisotropic two-orbital Hubbard model
- Fictive Impurity Approach to Dynamical Mean Field Theory: a Strong-Coupling Investigation
- Collective spin mode in a multi-component system of coupled itinerant and localized electrons
- Cluster Dynamical Mean-field calculations for TiOCl