Properties of a two orbital model for oxypnictide superconductors: Magnetic order, B_2g spin-singlet pairing channel, and its nodal structure

Abstract

A two orbital model for the new Fe-based superconductors is studied using the Lanczos method as well as pairing mean-field approximations. Our main goals are (i) to provide a comprehensive analysis of this model using numerical techniques with focus on half-filling and on the state with two more electrons than half-filling and (ii) to investigate the nodal structure of the mean-field superconducting state and compare the results with angle-resolved photoemission data. In particular, we provide evidence that at half-filling spin 'stripes', as observed experimentally, dominate over competing states. Depending on parameters, the state with two more electrons added to half filling is either triplet or singlet. Since experiments suggest spin singlet pairs, our focus is on this state. Under rotation, it transforms as the B_2g representation of the D_4h group. We also show that the s+/- pairing operator transforms as A_1g and becomes dominant only in an unphysical regime of the model where the undoped state is an insulator. For robust values of the effective electronic attraction producing the Cooper pairs, assumption compatible with recent angle-resolved photoemission (ARPES) results that suggesting small Cooper-pair size, the nodes of the two-orbital model are found to be located only at the electron pockets. Since recent ARPES efforts have searched for nodes at the hole pockets or only in a few directions at the electron pockets, our results for the nodal distribution may help to guide future experiments. More in general, the investigations reported here aim to establish several of the properties of the two orbital model. Only a detailed comparison with experiments will clarify how far this simple model present a valid description of the Fe pnictides.

References in corpus (73)

• Colossal Magnetoresistant Materials: The Key Role of Phase Separation
• Correlated Electrons in High Temperature Superconductors
• Unconventional sign-reversing superconductivity in LaFeAsO_(1-x)F_x
• Magnetic Order versus superconductivity in the Iron-based layered La(O1-xFx)FeAs systems
• Superconductivity at 43 K in Samarium-arsenide Oxides $SmFeAs{O}_{1-x}{F}_x$
• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• LaFeAsO${}_{1-x}$F${}_x$: A low carrier density superconductor near itinerant magnetism
• Superconductivity at 41 K and its competition with spin-density-wave instability in layered CeO${}_{1-x}$F${}_x$FeAs
• Observation of Fermi-surface-dependent nodeless superconducting gaps in Ba0.6K0.4Fe2As2
• Structural and magnetic phase diagram of CeFeAsO1-xFx and its relationship to high-temperature superconductivity
• Superconductivity and Phase Diagram in the Iron-based Arsenic-oxides ReFeAsO1-delta (Re = rare earth metal) without F-Doping
• Strong Correlations and Magnetic Frustration in the High Tc Iron Pnictides
• Competing Orders and Spin-Density-Wave Instability in La(O${}_{1-x}$F${}_x$)FeAs
• Is LaO${}_{1-x}$F${}_x$FeAs an electron-phonon superconductor ?
• Superconductivity at 25 K in hole doped $(L{a}_{1-x}S{r}_x)OFeAs$
• Origin of the ~150 K Anomaly in LaOFeAs; Competing Antiferromagnetic Superexchange Interactions, Frustration, and Structural Phase Transition
• Correlated electronic structure of LaOFeAs
• A minimal two-band model for the superconducting Fe-pnictides
• Coherence-incoherence crossover in the normal state of iron-oxypnictides and importance of the Hund's rule coupling
• Ising and Spin orders in Iron-based Superconductors
• Superconductivity at 52 K in iron-based F-doped layered quaternary compound Pr[O1-xFx]FeAs
• Pairing Symmetry in a Two-Orbital Exchange Coupling Model of Oxypnictides
• Spin-orbital frustrations and anomalous metallic state in iron-pnictide superconductors
• Coexistence of the spin-density-wave and superconductivity in the (Ba,K)Fe2As2
• Lattice and magnetic instabilities in CaFe2As2: A single crystal neutron diffraction study
• The BCS-like gap in superconductor SmFeAsO_0.85F_0.15
• Theory of magnetic excitations in iron-based layered superconductors
• Evolution from Itinerant Antiferromagnet to Unconventional Superconductor with Fluorine Doping in La(O_{1-x}F_{x})FeAs Revealed by ^{75}As and ^{139}La Nuclear Magnetic Resonance
• ${}^{75}$As NMR studies of superconducting LaO${}_{0.9}$F${}_{0.1}$FeAs
• 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
• Momentum dependence of the superconducting gap in NdFeAsO1-xFx single crystals measured by angle resolved photoemission spectroscopy
• Doping-dependent Phase Diagram of LaO{\it M}As ({\it M}=V--Cu) and Electron-type Superconductivity near Ferromagnetic Instability
• Microwave Penetration Depth and Quasiparticle Conductivity in PrFeAsO_1-y Single Crystals : Evidence for a Full-Gap Superconductor
• Electron Correlations in the Low Carrier Density LaFeAsO0.89F0.11 Superconductor (Tc = 28 K)
• Spin-singlet superconductivity with multiple gaps in PrO0.89F0.11FeAs
• Magnetic and structural transitions in layered FeAs systems: AFe2As2 versus RFeAsO compounds
• Bandwidth and Fermi surface of Iron-Oxypnictides: covalency and sensitivity to structural changes
• (pi,pi)-electronic order in iron arsenide superconductors
• Multiple Nodeless Superconducting Gaps in (Ba0.6K0.4)Fe2As2 Superconductor from Angle-Resolved Photoemission Spectroscopy
• NMR relaxation rate in superconducting pnictides: extended $s_{\pm }$ scenario
• Superconducting properties of Fe-based layered superconductor LaO${}_{0.9}$F${}_{0.1-\delta }$FeAs
• Model for the Magnetic Order and Pairing Channels in Fe Pnictide Superconductors
• Ab initio Derivation of Low-energy Model for Iron-Based Superconductors LaFeAsO and LaFePO
• Comparative High Field Magneto-Transport of Rare Earth Oxypnictides with Maximum Transition Temperatures
• Magnetic Order of the Iron Spins in NdOFeAs
• Superconductivity Near Phase Separation in Models of Correlated Electrons
• Even Parity, Orbital Singlet and Spin Triplet Pairing for Superconducting $La(O_{1-x}{F}_x)FeAs$
• 19-F NMR Investigation of Iron-pnictide Superconductor LaFeAsO(0.89)F(0.11)
• Coexistence of magnetic fluctuations and superconductivity in the pnictide high temperature superconductor SmFeAsO${}_{1-x}$F${}_x$ measured by muon spin rotation
• Point-Contact Spectroscopy of Iron-Based Layered Superconductor LaO${}_{0.9}$F${}_{0.1-\delta }$FeAs
• 75As NQR/NMR Studies on Oxygen-deficient Iron-based Oxypnictide Superconductors LaFeAsO_{1-y} (y=0,0.25,0.4) and NdFeAsO_{0.6}
• Experimental Consequences of the S-wave $\cos (k_x)\cdot \cos (k_y)$ Superconductivity in the Iron-Pnictides
• Superconducting Gap and Pseudogap in Iron-Based Layered Superconductor La(O${}_{1-x}$F${}_x$)FeAs
• A Generic Two-band Model for Unconventional Superconductivity and Spin-Density-Wave Order in Electron and Hole Doped Iron-Based Superconductors
• Competing orders in FeAs layers
• Scanning tunneling spectroscopy of SmFeAsO0.85: Possible evidence for d-wave order parameter symmetry
• Nodal Superconductivity with Multiple Gaps in SmFeAsO${}_{0.9}$F${}_{0.1}$
• Phonon Density of States of LaFeAsO1-xFx
• Magnetic and Metallic State at Intermediate Hubbard U Coupling in Multiorbital Models for Undoped Fe Pnictides
• Signatures of Electronic Correlations in Optical Properties of LaFeAsO${}_{1-x}$F${}_x$
• Phenomenological BCS theory of the high-$T_c$ cuprates
• Fermi Surface and Band Renormalization in (Sr,K)Fe${}_2$As${}_2$ Superconductor from Angle-Resolved Photoemission Spectroscopy
• Superconducting energy gap and c-axis plasma frequency of (Nd,Sm)O0.82F0.18FeAs superconductors from infrared ellipsometry
• Anisotropic pairing in the iron pnictides
• Enhanced Orbital Degeneracy in Momentum Space for LaOFeAs
• Inter-Band Pairing Theory of Superconductivity
• Possible unconventional superconductivity in iron-based layered compound LaFePO: Study of heat capacity
• Symmetry of superconducting states with two orbitals on a tetragonal lattice: application to $La{O}_{1-x}{F}_{x}FeAs$
• Coexistence of Supercondcutivity and Magnetism in LaFeAs(O0.94F0.06) Probed by Muon Spin Relaxation
• Effective Hamiltonian for FeAs based superconductors
• Effect of the tetrahedral distortion on the electronic properties of iron-pnictides
• Orbital Degeneracy and the Microscopic Model of the FeAs Plane in the Iron-Based Superconductors

Cited by in corpus (72)

• Antiferromagnetic order and spin dynamics in iron-based superconductors
• Magnetism and its microscopic origin in iron-based high-temperature superconductors
• High Temperature Superconductivity in Iron Pnictides and Chalcogenides
• Ferro-Orbital Order and Strong Magnetic Anisotropy in the Parent Compounds of Iron-Pnictide Superconductors
• Odd-frequency superconductivity
• Three orbital model for the iron-based superconductors
• Orbital Ordering and Unfrustrated $(\pi ,0)$ Magnetism from Degenerate Double Exchange in the Iron Pnictides
• Unified Picture for Magnetic Correlations in Iron-Based Superconductors
• Low-energy microscopic models for iron-based superconductors: a review
• Antiferroquadrupolar and Ising-Nematic Orders of a Frustrated Bilinear-Biquadratic Heisenberg Model and Implications for the Magnetism of FeSe
• Momentum dependence and nodes of the superconducting gap in iron-pnictides
• Odd-frequency superconducting pairing in multi-band superconductors
• U(1) Slave-spin theory and its application to Mott transition in a multi-orbital model for iron pnictides
• Evolution of symmetry and structure of the gap in Fe-based superconductors with doping and interactions
• Orbitally and Magnetically Induced Anisotropy in Iron-based Superconductors
• Neutron and ARPES Constraints on the Couplings of the Multiorbital Hubbard Model for the Pnictides
• Orbital selectivity and emergent superconducting state from quasi-degenerate $s-$ and $d-$wave pairing channels in iron-based superconductors
• Orbital selective pairing and superconductivity in iron selenides
• Electron-doping evolution of the low-energy spin excitations in the iron arsenide BaFe${}_{2-x}$Ni${}_x$As${}_2$ superconductors
• Magnetic States of the Two-Leg Ladder Alkali Metal Iron Selenides $A$Fe${}_2$Se${}_3$
• Nodeless energy gaps of single-crystalline Ba0.68K0.32Fe2As2 as seen via 75As NMR
• Orbital-weight redistribution triggered by spin order in the pnictides
• Competing Pairing Symmetries in a Generalized Two-Orbital Model for the Pnictides
• Tight binding model for iron pnictides
• Superconductivity at the Border of Electron Localization and Itinerancy
• On interband pairing in multiorbital systems
• Highly anisotropic energy gap in superconducting Ba(Fe${}_{0.9}$Co${}_{0.1}$)${}_2$As${}_2$ from optical conductivity measurements
• Theory of Multiband Superconductivity in Iron Pnictides
• Orbital selectivity in electron correlations and superconducting pairing of iron-based superconductors
• Superconductivity in Multi-orbital t-J1-J2 Model and its Implications for Iron Pnictides
• Anisotropic vortex lattice structures in the FeSe superconductor
• Magnetic order in orbital models of the iron pnictides
• The Josephson current in Fe-based superconducting junctions: theory and experiment
• Cross-band versus intra-band pairing in superconductors: signatures and consequences of the interplay
• Tuning between singlet, triplet, and mixed pairing states in an extended Hubbard chain
• Self-energy effects and electron-phonon coupling in Fe-As superconductors
• Properties of a diagonal 2-orbital ladder model of the Fe-pnictide superconductors
• Orbital-dependent effects of electron correlations in microscopic models for iron-based superconductors
• Vertical loop nodes in iron-based superconductors
• Spin-Density-Wave Gap with Dirac Nodes and Two-Magnon Raman Scattering in BaFe2As2
• Optical Conductivity Anisotropy in the Undoped Three-Orbital Hubbard Model for the Pnictides
• Pairing Symmetries of a Hole-Doped Extended Two-Orbital Model for the Pnictides
• A Twisted Ladder: relating the Fe superconductors to the high $T_c$ cuprates
• Charge Stripes in the Two-Orbital Hubbard Model for Pnictides
• Screening in a two-band model for superconducting infinite-layer nickelate
• Role of Degeneracy, Hybridization, and Nesting in the Properties of Multi-Orbital Systems
• Effective Exchange Interactions for Bad Metals and Implications for Iron-based Superconductors
• Spin dynamics in electron-doped pnictide superconductors
• Study of the magnetic state of K${}_{0.8}$Fe${}_{1.6}$Se${}_2$ using the five-orbital Hubbard model in the Hartree-Fock approximation
• A Two-band Model for p-wave Superconductivity
• Temperature dependence of the resonance and low energy spin excitations in superconducting FeTe${}_{0.6}$Se${}_{0.4}$
• On-site Atractive Multiorbital Hamiltonian for $d$-Wave Superconductors
• A Unified Description of Cuprate and Iron Arsenide Superconductors
• Electron Correlation and Spin Dynamics in Iron Pnictides and Chalcogenides
• Fermi surface pockets in electron-doped iron superconductor by Lifshitz transition
• The microscopic basis for phase-sensitive experiments for determination of the order parameter symmetry in Fe-based superconductors
• Superconductivity by Hidden Spin Fluctuations in Electron-Doped Iron Selenide
• Spin Resonances in Iron-Selenide High-Tc Superconductors by Proximity to Hidden Spin Density Wave
• Pairing mechanism in Fe pnictide superconductors
• Anisotropic magnetic excitations of a frustrated bilinear-biquadratic spin model -- Implications for spin waves of detwinned iron pnictides
• Constraints Imposed by Symmetry on Pairing Operators for the Pnictides
• Orbital Selective Directional Conductor in the Two Orbital Hubbard Model
• Coexistence of Pairing Tendencies and Ferromagnetism in a Doped Two-Orbital Hubbard Model on Two-Leg Ladders
• Ferroelectricity-induced multiorbital odd-frequency superconductivity in SrTiO${}_3$
• Finite Temperature Phase Diagrams of a Two-band Model of Superconductivity
• Magnetic and pairing properties of a two-orbital model for the pnictide superconductors: A quantum Monte Carlo study
• Resource-optimized fault-tolerant simulation of the Fermi-Hubbard model and high-temperature superconductor models
• Comment on "Nonmagnetic Impurity Resonances as a Signature of Sign-Reversal Pairing in Fe-As-Based Superconductors"
• Momentum distribution and non-Fermi liquid behaviour in low-doped two-orbital model: finite-size cluster quantum Monte Carlo approach
• Metal-insulator transition and superconductivity in the two-orbital Hubbard-Holstein model for iron-based superconductors
• Effects of order parameter self-consistency in a $s_{\pm }$-s junction
• Enhancing long-range order in disordered two-band s-wave superconductors