Theory for superconductivity in (Tl,K)Fe${}_x$Se${}_2$ as a doped Mott insulator

Abstract

Possible superconductivity in recently discovered (Tl,K)Fe${}_x$Se${}_2$ compounds is studied from the viewpoint of doped Mott insulator. The Mott insulating phase is examined to be preferred in the parent compound at $x=1.5$ due to the presence of Fe vacancies. Partial filling of vacancies at the Fe-sites introduces electron carriers and leads to electron doped superconductivity. By using a two-orbital Hubbard model in the strong coupling limit, we find that the s-wave pairing is more favorable at small Hund's coupling, and d${}_{x^2-y^2}$ wave pairing is more favorable at large Hund's coupling.

4+ pages, 3 figures, to appear in EPL

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Cited by in corpus (50)

• High Temperature Superconductivity in Iron Pnictides and Chalcogenides
• The Unexpected Properties of Alkali Metal Iron Selenide Superconductors
• Observation of Temperature-Induced Crossover to an Orbital-Selective Mott Phase in A${}_x$Fe${}_{2-y}$Se${}_2$ (A=K, Rb) Superconductors
• Anomalous correlation effects and unique phase diagram of electron doped FeSe revealed by angle resolved photoemission spectroscopy
• Plain s-wave superconductivity in single-layer FeSe on SrTiO3 probed by scanning tunneling microscopy
• Orbital-selective Mott Phase in Multiorbital Models for Alkaline Iron Selenides K(1-x)Fe(2-y)Se2
• Electronic identification of the actual parental phase of KxFe2-ySe2 superconductor and its intrinsic mesoscopic phase separation
• Interplay between magnetism and superconductivity in iron-chalcogenide superconductors: crystal growth and characterizations
• U(1) Slave-spin theory and its application to Mott transition in a multi-orbital model for iron pnictides
• Possible nodal superconducting gap emerging at the Lifshitz transition in heavily hole-doped Ba0.1K0.9Fe2As2
• Angle-resolved photoemission evidence of s-wave superconducting gap in KxFe2-ySe2 superconductor
• Electronic Evidence of an Insulator-Superconductor Transition in Single-Layer FeSe/SrTiO3 Films
• Superconductivity in the iron selenide KxFe2Se2 (0 <= x <= 1)
• New ternary ThCr2Si2-type iron-selenide superconducting materials: synthesis, properties and simulations
• Block Spin Ground State and 3-Dimensionality of (K,Tl)Fe${}_{1.6}$Se${}_2$
• Robustness of s-wave Pairing in Electron-Overdoped ${\text{A}}_{1-y}{\text{Fe}}_{2-x}{\text{Se}}_2$
• Surface electronic structure and evidence of plain s-wave superconductivity in (Li0.8Fe0.2)OHFeSe
• Superconductivity at the Border of Electron Localization and Itinerancy
• Spin Dynamics of a J1-J2-K Model for the Paramagnetic Phase of Iron Pnictides
• Structural, Magnetic and Electronic Properties of the Iron-Chalcogenide A${}_x$Fe${}_{2-y}$Se${}_2$ (A=K, Cs, Rb, Tl and etc.) Superconductors
• The magnetic phase diagram of an extended J1-J2 model on a modulated square lattice and its implications for the antiferromagnetic phase of KyFexSe2
• Unconventional Mott Transition in KxFe2-ySe2
• An extensive impurity-scattering study on the pairing symmetry of monolayer FeSe films on SrTiO3
• Heterostructural one-unit-cell FeSe/SrTiO3: from high-temperature superconductivity to topological states
• Local Electronic Structure around a Single Impurity as a Test of Pairing Symmetry in (K,Tl)Fe${}_x$Se${}_2$ Superconductors
• Phase diagram and a possible unified description of intercalated iron selenide superconductors
• Bandwidth and Electron Correlation-Tuned Superconductivity in Rb${}_{0.8}$Fe${}_2$(Se${}_{1-z}$S${}_z$)${}_2$
• Lattice distortion induced first and second order topological phase transition in rectangular high-T${}_{\mathrm{c}}$ superconducting monolayer
• Vacancy Driven Orbital and Magnetic Order in (K,Tl,Cs)${}_y$Fe${}_{2-x}$Se${}_2$
• Evolution of superconductivity in isovalent Te-substituted KxFe2-ySe2 crystals
• Exploration of iron-chalcogenide superconductors
• ARPES observation of isotropic superconducting gaps in isovalent Ru-substituted Ba(Fe${}_{0.75}$Ru${}_{0.25}$)${}_2$As${}_2$
• Intrinsic high-temperature superconductivity in ternary iron selenides
• Possible pairing symmetry in the FeSe-based superconductors determined by quasiparticle interference
• Electronic structure of vacancy-ordered iron-selenide K${}_{0.5}$Fe${}_{1.75}$Se${}_2$
• Superconducting proximity effect to the block antiferromagnetism in K${}_y$Fe${}_{2-x}$Se${}_2$
• Effective tight-binding model for the iron vacancy ordered A${}_y$FeSe${}_2$
• Angle-resolved photoemission studies of the superconducting gap symmetry in Fe-based superconductors
• Resonance states near a quantum magnetic impurity in single-layer FeSe superconductors with $d$-wave symmetry
• Dynamic approach to finite-temperature magnetic phase transitions in the extended J1- J2 model with vacancy order
• A minimum single-band model for low-energy excitations in superconducting K${}_x$Fe${}_2$Se${}_2$
• Fermi surface evolution and checker-board block-spin antiferromagnetism in $A_x$Fe${}_{2-y}$Se${}_2$
• Orbital-resolved vortex core states in FeSe Superconductors: calculation based on a three-orbital model
• Unconventional superconducting gap via spin fluctuations in iron-vacancy ordered A${}_y$Fe${}_{2-x}$Se${}_2$
• In-gap bound states induced by a single nonmagnetic impurity in sign-preserving s-wave superconductors with incipient bands
• Metal-insulator transition and superconductivity in the two-orbital Hubbard-Holstein model for iron-based superconductors
• Generalized joint density of states and its application to exploring the pairing symmetry of superconductors
• Temperature and doping dependence of normal state spectral properties in a two-orbital model for ferropnictides
• Pairing Symmetry and Spin Excitations of Iron Selenide Superconductors
• Fe-vacancy ordered Fe4Se5: The insulating parent phase of FeSe superconductor