Correlation-induced self-doping in intercalated iron-pnictide superconductor Ba2Ti2Fe2As4O

Abstract

The electronic structure of the intercalated iron-based superconductor Ba2Ti2Fe2As4O (Tc - 21.5 K) has been investigated by using angle-resolved photoemission spectroscopy and combined local density approximation and dynamical mean field theory calculations. The electronic states near the Fermi level are dominated by both the Fe 3d and Ti 3d orbitals, indicating that the spacing layers separating different FeAs layers are also metallic. By counting the enclosed volumes of the Fermi surface sheets, we observe a large self-doping effect, i.e. 0.25 electrons per unit cell are transferred from the FeAs layer to the Ti2As2O layer, leaving the FeAs layer in a hole-doped state. This exotic behavior is successfully reproduced by our dynamical mean field calculations, in which the self-doping effect is attributed to the electronic correlations in the Fe 3d shell. Our work provides an alternative route of effective doping without element substitution for iron-based superconductors.

5 pages, 3 figures + Supplementary material

References in corpus (22)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Superconductivity at 22 K in Co-doped BaFe2As2 Crystals
• Dynamical Mean-Field Theory within an Augmented Plane-Wave Framework: Assessing Electronic Correlations in the Iron Pnictide LaFeAsO
• Superconductivity up to 30 K in the vicinity of quantum critical point in BaFe${}_2$(As${}_{1-x}$P${}_x$)${}_2$
• A precise method for visualizing dispersive features in image plots
• Theoretical evidence for strong correlations and incoherent metallic state in FeSe
• Satellites and large doping- and temperature-dependence of electronic properties in hole-doped BaFe2As2
• Fe-based superconductors: an angle-resolved photoemission spectroscopy perspective
• Electron doped Ca10(Pt3As8)(Fe2As2)5 and Ca10(Pt4As8)(Fe2As2)5 - High Tc superconductors with skutterudite intermediary layers
• Superconductivity in Ru substituted BaFe2-xRuxAs2
• Electronic structure of optimally doped pnictide Ba${}_{0.6}$K${}_{0.4}$Fe${}_2$As${}_2$: a comprehensive ARPES investigation
• Superconductivity up to 35 K in the iron-platinum arsenides (CaFe1-xPtxAs)10Pt4-yAs8 with layered structures
• Superconductivity induced by ruthenium substitution in an iron arsenide: investigation of SrFe2-xRuxAs2 (0 <= x <= 2)
• Extraordinary quasiparticle scattering and bandwidth-control by dopants in iron-based superconductors
• Gutzwiller density functional calculations of the electronic structure of FeAs-based superconductors: Evidence for a three-dimensional Fermi surface
• Dynamical correlations and screened exchange on the experimental bench: spectral properties of the cobalt pnictide BaCo2As2
• Normal-state charge dynamics in doped BaFe2As2: Roles of doping and necessary ingredients for superconductivity
• Self doping effect and successive magnetic transitions in superconducting Sr${}_2$VFeAsO${}_3$
• Electronic band structure of BaCo${}_2$As${}_2$: a fully-doped ferropnictide with reduced electronic correlations
• Universal pair-breaking in transition metal-substituted iron-pnictide superconductors
• Electronic structure of the BaTi${}_2$As${}_2$O parent compound of the titanium based oxypnictide superconductor
• Effects of metallic spacer in layered superconducting Sr2(Mg${}_y$Ti${}_{1-y}$)O3FeAs

Cited by in corpus (11)

• Superconductivity and Ferromagnetism in Hole-Doped RbEuFe${}_4$As${}_4$
• Coulomb Correlations in 4d and 5d Oxides from First Principles - or How Spin-Orbit Materials choose their Effective Orbital Degeneracies
• Structural and magnetic phase transitions in Ca${}_{0.73}$La${}_{0.27}$FeAs${}_2$ with electron overdoped FeAs layers
• Hubbard interactions in iron-based pnictides and chalcogenides: Slater parametrization, screening channels and frequency dependence
• Spectral functions of Sr${}_2$IrO${}_4$: theory versus experiment
• Low-energy effective Hamiltonians for correlated electron systems beyond density functional theory
• Electronic correlations at paramagnetic $(001)$ and $(110)$ NiO surfaces: Charge-transfer and Mott-Hubbard-type gaps at the surface and subsurface of $(110)$ NiO
• Self-Optimized Superconductivity Attainable by Interlayer Phase Separation at Cuprate Interfaces
• Mössbauer spectroscopy study of magnetic fluctuations in superconducting RbGd${}_2$Fe${}_4$As${}_4$O${}_2$
• Absence of magnetism in the superconductor Ba2Ti2Fe2As4O: Insights from inelastic neutron scattering measurements and ab initio calculations of phonon spectra
• Novel approaches to spectral properties of correlated electron materials: From generalized Kohn-Sham theory to screened exchange dynamical mean field theory