Understanding doping, vacancy, lattice stability and superconductivity in KxFe2-ySe2

Abstract

Metal-intercalated iron selenides are a class of superconductors that have received much attention but are less understood in comparison with their FeAs-based counterparts. Here, the controversial issues such as Fe vacancy, the real phase responsible for superconductivity, and lattice stability have been addressed based on first-principles calculations. New insights into the distinct features in terms of carrier doping have been revealed.

References in corpus (20)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• Superconductivity in single-layer films of FeSe with a transition temperature above 100 K
• The superconductivity at 18 K in LiFeAs system
• Superconductivity up to 37 K in (A1-xSrx)Fe2As2 with A=K and Cs
• LiFeAs: An Intrinsic FeAs-based Superconductor with Tc = 18K
• Magnetism and its microscopic origin in iron-based high-temperature superconductors
• Heavily electron-doped electronic structure and isotropic superconducting gap in AxFe2Se2 (A=K,Cs)
• Fe-based high temperature superconductivity with Tc=31K bordering an insulating antiferromagnet in (Tl,K)FexSe2 Crystals
• Superconductivity and Crystal Structures of (Ba1-xKx)Fe2As2 (x = 0 - 1)
• Superconductivity at 32 K in single crystal Rb${}_{0.78}$Fe${}_2$Se${}_{1.78}$}
• Superconducting Phases in Potassium-Intercalated Iron Selenides
• Superconductivity at 32K and anisotropy in Tl0.58Rb0.42Fe1.72Se2 crystals
• High temperature superconducting FeSe films on SrTiO3 substrates
• Phase relations in K_xFe_{2-y}Se_2 and the structure of superconducting K_xFe_2Se_2 via high-resolution synchrotron diffraction
• Superconductivity and phase instability of NH3-free Na-intercalated FeSe1-zSz
• Superconductivity at 44 K in K intercalated FeSe system with excess Fe
• Effective doping and suppression of Fermi surface reconstruction via Fe vacancy disorder in KxFe2-ySe2
• Spectromicroscopy of electronic phase separation in K${}_x$Fe${}_{2-y}$Se${}_2$ superconductor
• Density Functional Study of the Over-Doped Iron Chalcogenide: TlFe${}_2$Se${}_2$ with ThCr${}_2$Si${}_2$ structure
• Overview on the physics and materials of the new superconductor KxFe2-ySe2