Effects of cobalt doping and three-dimensionality in $BaF{e}_{2}A{s}_2$

Abstract

We investigate the dual roles of a cobalt impurity in the Ba-122 ferropnictide superconductor in the state with coexisting collinear spin density wave (SDW) order as a dopant and as a scattering center, using first principles electronic structure methods. The Co atom is found to dope the FeAs plane where it is located with a single delocalized electron as expected, but also induces a strong perturbation of the SDW ground state of the system. This in turn induces a stripe-like modulation of the density of states in nearby planes which may be observable in STM experiments. The defect is found to have an intermediate strength nonmagnetic scattering potential with a range of roughly 1 Angstrom, and the Co gives rise to a smaller but longer range magnetic scattering potential. The impurity potential in both channels is highly anisotropic, reflecting the broken symmetry of the SDW ground state. We give values for the effective Co potentials for each d orbital on the impurity and nearby sites. The calculation also shows a clear local resonance comprised of Co states about 200meV above the Fermi level, in quantitative agreement with a recent report from STM. Finally, we discuss the issue of the effective dimensionality of the 122 materials, and show that the hybridization of the out-of-phase As atoms leads to a higher density of states between the FeAs planes relative to the 1111 counterparts.

References in corpus (30)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Unconventional sign-reversing superconductivity in LaFeAsO_(1-x)F_x
• Unconventional pairing originating from disconnected Fermi surfaces in superconducting LaFeAsO${}_{1-x}$F${}_x$}
• Superconductivity at 22 K in Co-doped BaFe2As2 Crystals
• Spin density wave anomaly at 140 K in the ternary iron arsenide BaFe2As2
• Magnetic order in BaFe2As2, the parent compound of the FeAs based superconductors in a new structural family
• Near-degeneracy of several pairing channels in multiorbital models for the Fe-pnictides
• Magnetism, superconductivity, and pairing symmetry in Fe-based superconductors
• Effects of Co substitution on thermodynamic and transport properties and anisotropic $H_{c2}$ in Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$ single crystals
• Determination of the phase diagram of the electron doped superconductor Ba(Fe${}_{1-x}$Co${}_x$)${}_2$As${}_2$
• Defects in correlated metals and superconductors
• Funtional Renormalization Group Study of the Pairing Symmetry and Pairing Mechanism of the FeAs Based High Temperature Superconductors
• A Numerical Renormalization Group Study of the Superconducting and Spin Density Wave Instabilities in MFeAsO${}_{1-x}$F${}_x$ Compounds
• Electronic Structure and Doping in BaFe${}_2$As${}_2$ and LiFeAs: Density Functional Calculations
• Anisotropic thermodynamic and transport properties of single crystalline (Ba${}_{1-x}$K${}_x$)Fe${}_2$As${}_2$ (x = 0 and 0.45)
• Proximity of antiferromagnetism and superconductivity in LaO${}_{1-x}$F${}_x$FeAs: effective Hamiltonian from ab initio studies
• Superconductivity in SrFe_(2-x)Co_xAs_2: Internal Doping of the Iron Arsenide Layers
• Spin and Lattice Structure of Single Crystal SrFe2As2
• Anisotropy of the Optimally-Doped Iron Pnictide Superconductor Ba(Fe0.926Co0.074)2As2
• Spin susceptibility, phase diagram, and quantum criticality in the electron-doped high Tc Superconductor Ba[Fe(1-x)Co(x)]2As2
• Spin Fluctuations, Interband Coupling, and Unconventional Pairing in Iron-based Superconductors
• AFe2As2 (A = Ca, Sr, Ba, Eu) and SrFe_(2-x)TM_(x)As2 (TM = Mn, Co, Ni): crystal structure, charge doping, magnetism and superconductivity
• Renormalized behavior and proximity to a magnetic quantum critical point in BaCo${}_2$As${}_2$
• The London penetration depth in single crystals of Ba(Fe_{1-x}Co_x)_2As_2 at various doping levels
• Possible pairing states of the Fe-based superconductors
• Anisotropic London Penetration Depth and Superfluid Density in Single Crystals of Iron-based Pnictide Superconductors
• Anisotropic pairing in the iron pnictides
• On superconducting and magnetic properties of iron-oxypnictides
• Ab Initio Calculation of Impurity Effects in Copper Oxide Materials
• Competition/Coexisitence of Magnetism and Superconductivity in Iron Pnictides Probed by Muon Spin Rotation

Cited by in corpus (46)

• Gap symmetry and structure of Fe-based superconductors
• Uniaxial strain detwinning of CaFe2As2 and BaFe2As2: optical and transport study
• Violation of Anderson's Theorem for Sign-Reversing s-Wave State of Iron-Pnictide Superconductors
• Spin fluctuations and superconductivity in a 3D tight-binding model for BaFe2As2
• Using Gap Symmetry and Structure to Reveal the Pairing Mechanism in Fe-based Superconductors
• Where Are the Extra d Electrons in Transition-Metal Substituted Fe Pnictides?
• Nodes in the gap structure of the iron-arsenide superconductor Ba(Fe_{1-x}Co_x)_2As_2 from c-axis heat transport measurements
• Disorder induced transition between s_+- and s_++ states in two-band superconductors
• Anisotropic Impurity-States, Quasiparticle Scattering and Nematic Transport in Underdoped Ca(Fe1-xCox)2As2
• Two types of s-wave pairing due to magnetic and orbital fluctuations in the two-dimensional 16-band d-p model for iron-based superconductors
• Using controlled disorder to distinguish $s_{\pm }$ and $s_{++}$ gap structure in Fe-based superconductors
• First-principles calculation of transition-metal impurities in LaFeAsO
• Suppression of the critical temperature of superconducting NdFeAs(OF) single crystals by Kondo-like defect sites induced by alpha-particle irradiation
• Co-substitution effects on the Fe-valence in the BaFe2As2 superconducting compound: A study of hard x-ray absorption spectroscopy
• Effect of tensile stress on the in-plane resistivity anisotropy in BaFe2As2
• In-Gap Quasiparticle Excitations Induced by Non-Magnetic Cu Impurities in Na(Fe0.96Co0.03Cu0.01)As Revealed by Scanning Tunneling Spectroscopy
• Effect of doping on the magnetostructural ordered phase of iron arsenides: A comparative study of the resistivity anisotropy in the doped BaFe${}_2$As${}_2$ with doping into three different sites
• Impurities in multiband superconductors
• Effect of 3d-doping on the electronic structure of BaFe2As2
• Local Magnetic Inhomogeneities in Lightly Doped BaFe${}_2$As${}_2$
• Origin of electronic dimers in the spin-density wave phase of Fe-based superconductors
• Complex state induced by impurities in multiband superconductors
• Impurity states in multiband s-wave superconductors: analysis of iron pnictides
• Unexpected weak spatial variation of local density of sates induced by individual Co impurity atoms in Na(Fe{1-x}Cox)As as revealed by scanning tunneling spectroscopy
• Effects of disordered Ru substitution in BaFe${}_2$As${}_2$: Realization of superdiffusion mechanism in real materials
• Single particle tunneling spectroscopy and superconducting gaps in layered iron based superconductor KCa${}_2$Fe${}_4$As${}_4$F${}_2$
• Cooperative effects of Coulomb and electron-phonon interactions in the two-dimensional 16-band d-p model for iron-based superconductors
• Effect of realistic finite-size impurities on Tc in Fe-based superconductors based on the five-orbital tight-binding model
• Commensurate antiferromagnetic ordering in Ba(Fe{1-x}Co{x})2As2 determined by x-ray resonant magnetic scattering at the Fe K-edge
• Transport properties of 3D extended s-wave states in Fe-based superconductors
• Nodal superconductivity in isovalently substituted SrFe${}_2$(As${}_{1-x}$P${}_x$)${}_2$ pnictide superconductor at the optimal doping, $x=$0.35
• Tunneling spectroscopy for probing orbital anisotropy in iron pnictides
• Consistent picture for the electronic structure around a vortex core in iron-based superconductors
• Time-reversal symmetry breaking state in dirty three-band superconductor
• Revealing the degree of magnetic frustration by non-magnetic impurities
• Highly anisotropic quasiparticle interference patterns in the spin-density wave state of the iron pnictides
• Dimer Impurity Scattering, "Reconstructed" Nesting and Density-Wave Diagnostics in Iron Pnictides
• Substitution of Ni for Fe in superconducting Fe${}_{0.98}$Te${}_{0.5}$Se${}_{0.5}$ depresses the normal-state conductivity but not the magnetic spectral weight
• The effect of disorder on electronic Raman scattering in the superconducting state of iron pnictides
• Evidence of the isoelectronic character of F doping in SmFeAsO(1-x)F(x): a first-principles investigation
• Effect of electron doping in FeTe${}_{1-y}$Se${}_y$ realized by Co and Ni substitution
• Non-rigid band shift and non-monotonic electronic structure changes upon doping in the normal state of the pnictide high temperature superconductor Ba2(Fe1-xCox)2As2
• RKKY coupled local moment magnetism in NaFe${}_{1-x}$Cu${}_x$As
• Effect of transition-metal substitution in iron-based superconductors
• A non-iterative method for the vertex corrections of the Kubo formula for electric conductivity
• Anomalous impurity effect in the heavy-fermion superconductor CeCu2Si2