Low magnetization and anisotropy in the antiferromagnetic state of undoped iron pnictides

Abstract

We examine the magnetic phase diagram of iron pnictides using a five band model. For the intermediate values of the interaction expected to hold in the iron pnictides, we find a metallic low moment state characterized by antiparallel orbital magnetic moments. The anisotropy of the interorbital hopping amplitudes is the key to understanding this low moment state. This state accounts for the small magnetization measured in undoped iron pnictides and leads to the strong exchange anisotropy found in neutron experiments. Orbital ordering is concomitant with magnetism and produces the large zx orbital weight seen at Gamma in photoemission experiments.

4 pages, 4 eps figures. Small changes in the text. Modification of colors in Figs. Final version as accepted in PRL

References in corpus (10)

• Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
• Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides
• Effect of Structural Parameters on Superconductivity in Fluorine-Free LnFeAsO1-y (Ln=La,Nd)
• Origin of the ~150 K Anomaly in LaOFeAs; Competing Antiferromagnetic Superexchange Interactions, Frustration, and Structural Phase Transition
• A minimal two-band model for the superconducting Fe-pnictides
• The challenge of unravelling magnetic properties in LaFeAsO
• Spin-orbital frustrations and anomalous metallic state in iron-pnictide superconductors
• Magnetic and Metallic State at Intermediate Hubbard U Coupling in Multiorbital Models for Undoped Fe Pnictides
• Tight binding model for iron pnictides
• Low ordered magnetic moment by off-diagonal frustration in undoped parent compounds to iron-based high-Tc superconductors

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• Low-energy microscopic models for iron-based superconductors: a review
• On the multi-orbital band structure and itinerant magnetism of iron-based superconductors
• Orbital Fluctuation Theory in Iron Pnictides: Effects of As-Fe-As Bond Angle, Isotope Substitution, and $Z^2$-Orbital Pocket on the Superconductivity
• Neutron and ARPES Constraints on the Couplings of the Multiorbital Hubbard Model for the Pnictides
• Conductivity anisotropy in the antiferromagnetic state of iron pnictides
• Orbital differentiation and the role of orbital ordering in the magnetic state of Fe superconductors
• Optical conductivity and Raman scattering of iron superconductors
• Spin-orbital interplay and topology in the nematic phase of iron pnictides
• Magnetic order in orbital models of the iron pnictides
• Correlation, doping and interband effects on the optical conductivity of iron superconductors
• Importance of Itinerancy and Quantum Fluctuations for the Magnetism in Iron Pnictides
• Breakdown of the Hund's Rule in CuFeAs
• Magnetism and Superconductivity in Iron-based Superconductors Decided by Condensed Particle-hole Excitations away from the Fermi Level