Orbital Order, Metal Insulator Transition, and Magnetoresistance-Effect in the two-orbital Hubbard model
arXiv:1011.2250 · doi:10.1103/PhysRevB.83.125110
Abstract
We study the effects of temperature and magnetic field on a two-orbital Hubbard model within dynamical mean field theory. We focus on the quarter filled system, which is a special point in the phase diagram due to orbital degeneracy. At this particular filling the model exhibits two different long-range order mechanisms, namely orbital order and ferromagnetism. Both can cooperate but do not rely on each other's presence, creating a rich phase diagram. Particularly, in the vicinity of the phase transition to an orbitally ordered ferromagnetic state, we observe a strong magnetoresistance effect. Besides the low temperature phase transitions, we also observe a crossover between a paramagnetic insulating and a paramagnetic metallic state for increasing Hund's coupling at high temperatures.
arXiv comment7 pages, 7 figures
References in corpus (19)
- The numerical renormalization group method for quantum impurity systems
- Anomalous Normal-State Properties of High-T Superconductors -- Intrinsic Properties of Strongly Correlated Electron Systems?
- Sum-rule Conserving Spectral Functions from the Numerical Renormalization Group
- A Numerical Renormalization Group approach to Green's Functions for Quantum Impurity Models
- Microscopic conditions favoring itinerant ferromagnetism: Hund's rule coupling and orbital degeneracy
- Hund's coupling and the metal-insulator transition in the two-band Hubbard model
- Metal-Insulator phase diagram and orbital selectivity in 3-orbital models with rotationally invariant Hund coupling
- Ferromagnetism in the Hubbard model with orbital degeneracy in infinite dimensions
- Multi-Orbital Hubbard Model in Infinite Dimensions: Quantum Monte Carlo Calculation
- Structural relaxation due to electronic correlations in the paramagnetic insulator KCuF3
- Stability of a metallic state in the two-orbital Hubbard model
- Effect of a magnetic field on Mott-Hubbard systems
- Magnetism and orbital-ordering in an interacting three band model: a dynamical mean field study
- Quantum Monte Carlo study for multiorbital systems with preserved spin and orbital rotational symmetries
- From Slater to Mott-Heisenberg physics: The antiferromagnetic phase of the Hubbard model
- Mott transitions in two-orbital Hubbard systems
- Magnetic groundstates in a correlated two orbital Hubbard model
- Itinerant ferromagnetism in the multiorbital Hubbard model: a dynamical mean-field study
- Spatial fluctuations of spin and orbital in two-orbital Hubbard model
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