On the multi-orbital band structure and itinerant magnetism of iron-based superconductors

Abstract

This paper explains the multi-orbital band structures and itinerant magnetism of the iron-pnictide and chalcogenides. We first describe the generic band structure of an isolated FeAs layer. Use of its Abelian glide-mirror group allows us to reduce the primitive cell to one FeAs unit. From density-functional theory, we generate the set of eight Fe $d$ and As $p$ localized Wannier functions for LaOFeAs and their tight-binding (TB) Hamiltonian, $h(k)$. We discuss the topology of the bands, i.e. allowed and avoided crossings, the origin of the d6 pseudogap, as well as the role of the As $p$ orbitals and the elongation of the FeAs${}_4$ tetrahedron. We then couple the layers, mainly via interlayer hopping between As $p_z$ orbitals, and give the formalism for simple and body-centered tetragonal stackings. This allows us to explain the material-specific 3D band structures. Due to the high symmetry, several level inversions take place as functions of $k_z$ or pressure, resulting in linear band dispersions (Dirac cones). The underlying symmetry elements are, however, easily broken, so that the Dirac points are not protected, nor pinned to the Fermi level. From the paramagnetic TB Hamiltonian, we form the band structures for spin spirals with wavevector $q$ by coupling $h(k)$ and $h(k+q)$. The band structure for stripe order is studied as a function of the exchange potential, $\Delta$, using Stoner theory. Gapping of the Fermi surface (FS) for small $\Delta$ requires matching of FS dimensions (nesting) and $d$-orbital characters. The origin of the propeller-shaped FS is explained. Finally, we express the magnetic energy as the sum over band-structure energies, which enables us to understand to what extent the magnetic energies might be described by a Heisenberg Hamiltonian, and the interplay between the magnetic moment and the elongation of the FeAs4 tetrahedron.

References in corpus (61)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• High-temperature superconductivity in iron-based materials
• LaFeAsO${}_{1-x}$F${}_x$: A low carrier density superconductor near itinerant magnetism
• Observation of Fermi-surface-dependent nodeless superconducting gaps in Ba0.6K0.4Fe2As2
• Density functional study of FeS, FeSe and FeTe: Electronic structure, magnetism, phonons and superconductivity
• LiFeAs: An Intrinsic FeAs-based Superconductor with Tc = 18K
• Magnetism, superconductivity, and pairing symmetry in Fe-based superconductors
• To What Extent Iron-Pnictide New Superconductors Have Been Clarified: A Progress Report
• Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides
• Theory of Electron Nematic Order in LaOFeAs
• Thorium-doping induced superconductivity up to 56 K in Gd1-xThxFeAsO
• Effect of Structural Parameters on Superconductivity in Fluorine-Free LnFeAsO1-y (Ln=La,Nd)
• Is LaO${}_{1-x}$F${}_x$FeAs an electron-phonon superconductor ?
• Origin of the ~150 K Anomaly in LaOFeAs; Competing Antiferromagnetic Superexchange Interactions, Frustration, and Structural Phase Transition
• Funtional Renormalization Group Study of the Pairing Symmetry and Pairing Mechanism of the FeAs Based High Temperature Superconductors
• Electronic Structure and Doping in BaFe${}_2$As${}_2$ and LiFeAs: Density Functional Calculations
• The challenge of unravelling magnetic properties in LaFeAsO
• Pressure-induced volume-collapsed tetragonal phase of CaFe2As2 as seen via neutron scattering
• Dynamical Mean-Field Theory within an Augmented Plane-Wave Framework: Assessing Electronic Correlations in the Iron Pnictide LaFeAsO
• Lattice and magnetic instabilities in CaFe2As2: A single crystal neutron diffraction study
• Multiband magnetism and superconductivity in Fe-based compounds
• Electron-Hole Symmetry and Magnetic Coupling in Antiferromagnetic LaOFeAs
• Magnetism and Charge Dynamics in Iron Pnictides
• The Unprecedented Giant Coupling of Fe-spin State and the As-As Hybridization in Iron-Pnictide
• Nodal Spin Density Wave and band topology of the FeAs based materials
• Proximity of antiferromagnetism and superconductivity in LaO${}_{1-x}$F${}_x$FeAs: effective Hamiltonian from ab initio studies
• Theoretical evidence for strong correlations and incoherent metallic state in FeSe
• Antiferromagnetic superexchange interactions in LaOFeAs
• Bandwidth and Fermi surface of Iron-Oxypnictides: covalency and sensitivity to structural changes
• Momentum dependence of the superconducting gap in Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$
• (pi,pi)-electronic order in iron arsenide superconductors
• Fermi surface of superconducting LaFePO determined by quantum oscillations
• A possible ground state and its electronic structure of a mother material (LaOFeAs) of new superconductors
• Itinerant magnetic excitations in antiferromagnetic CaFe2As2
• A Systematic Study of Electron-Phonon Coupling to Oxygen Modes Across the Cuprates
• Where Are the Extra d Electrons in Transition-Metal Substituted Fe Pnictides?
• Quantum oscillations in the parent magnetic phase of an iron arsenide high temperature superconductor
• Unconventional electronic reconstruction in undoped (Ba,Sr)Fe${}_2$As${}_2$ across the spin density wave transition
• Dichotomy between large local and small ordered magnetic moment in Iron-based superconductors
• Effects of magnetism and doping on the electron-phonon coupling in BaFe${}_2$As${}_2$
• Electronic Structure of the BaFe${}_2$As${}_2$ Family of Iron Pnictides
• Quantum oscillations in the parent pnictide BaFe${}_2$As${}_2$ : itinerant electrons in the reconstructed state
• Interplay between magnetic properties and Fermi surface nesting in iron pnictides
• Classification of the electronic correlation strength in the Fe-pnictides: The case of the parent compound BaFe2As2
• First Homologous Series of Iron Pnictide Oxide Superconductors (Fe2As2)(Can+1(Sc,Ti)nOy) [n = 3,4,5] with Extremely Thick Blocking Layers
• Fermi surface of SrFe${}_2$P${}_2$ determined by de Haas-van Alphen effect
• Low magnetization and anisotropy in the antiferromagnetic state of undoped iron pnictides
• Ab initio lattice dynamics simulations and inelastic neutron scattering spectra for studying phonons in BaFe2As2: Effect of structural phase transition, structural relaxation and magnetic ordering
• ARPES studies of the electronic structure of LaOFe(P,As)
• Signatures of Electronic Correlations in Optical Properties of LaFeAsO${}_{1-x}$F${}_x$
• Topological change of the Fermi surface in ternary iron-pnictides with reduced c/a ratio: A dHvA study of CaFe2P2
• Pinpointing Gap Minima in Ba(Fe${}_{0.94}$Co${}_{0.06}{)}_2$As${}_2$ \textit{via} Band Structure Calculations and Electronic Raman Scattering
• The Delicate Electronic and Magnetic Structure of the LaOFePn System (Pn = pnictogen)
• Determining gap nodal structures in Fe-based superconductors: angle-dependence of the low temperature specific heat in an applied magnetic field
• Electronic structure of Ba(Fe,Ru)2As2 and Sr(Fe,Ir)2As2 alloys
• Multiple Gaps and Superfluid Density from Interband Pairing in Iron Oxypnictides
• Analysis of spin density wave conductivity spectra of iron pnictides in the framework of density functional theory
• Fermi surface and strong coupling superconductivity in single crystal NdFeAsO_{1-x}F_x
• Why some Iron-based superconductors are nodal while others are nodeless

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• Towards a quantitative description of tunneling conductance of superconductors: application to LiFeAs
• Tuning electronic correlations in transition metal pnictides: chemistry beyond the valence count
• Effects of Lifshitz Transition on Charge Transport in Magnetic Phases of Fe-Based Superconductors
• Accurate bare susceptibilities from full-potential $\text{ab initio}$ calculations
• Heavy Electron doping-induced antiferromagnetic phase as the parent for iron-oxypnictide superconductor LaFeAsO1-xHx
• Effect of Ru susbstitution on atomic displacements in the layered SmFe_{1-x}Ru_xAsO_{0.85}F_{0.15} superconductor
• Highly mobile carriers in orthorhombic phases of iron-based superconductors FeSe${}_{1-x}$S${}_x$
• Glide-Plane Symmetry and Superconducting Gap Structure of Iron-Based Superconductors
• FeSe and the missing electron pocket problem
• Origin of the non-monotonic variance of Tc in the 1111 iron based superconductors with isovalent doping
• Double-degenerate Fermi mixtures of ${}^6$Li and ${}^{53}$Cr atoms
• First-principles theory of electron-spin fluctuation coupling and superconducting instabilities in iron selenide
• Structural, electronic, and dynamical properties of the tetragonal and collapsed tetragonal phases of KFe${}_2$As${}_2$
• Orbital Symmetry and Orbital Excitations in High-$T_c$ Superconductors
• Theoretical investigation of the electronic and magnetic properties of the orthorhombic phase of Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Influence of the surface symmetry breaking on the magnetism, collapsing and three dimensional dispersion of Co pnictides ACo2As2 (A=Ba, Sr, Ca)
• Semimetallic spin-density wave state in iron pnictides
• Effect of the iron valence in the two types of layers in LiFeO${}_2$Fe${}_2$Se${}_2$