Pairing Symmetry in Iron-Pnictide Superconductor KFe${}_2$As${}_2$

Abstract

The pairing symmetry is one of the major issues in the study of iron-based superconductors. We adopt a low-energy effective kinetic model based on the first-principles band structure calculations combined with the $J_1$-$J_2$ model for KFe${}_2$As${}_2$, the phase diagram of pairing symmetries is constructed. Putting the values of $J_1$ and $J_2$ of the $J_1$-$J_2$ model obtained by the first-principles calculations into this phase diagram, we find that the pairing symmetry for KFe${}_2$As${}_2$ is a nodal $d_{xy}$-wave in the folded Brillouin zone with two iron atoms per unit cell. This is in good agreement with experiments observed a nodal order parameter.

5 pages, 4 figures (The pairing symmetry is dependent on choosing an effective tight-binding model. In the publication version, we adopt a ten-orbital model by using the maximally localized Wannier functions based on the first-principles band structure calculations, and give an s-wave pairing for KFe${}_2$As${}_2$)

References in corpus (17)

• Superconductivity at 38 K in the iron arsenide (Ba1-xKx)Fe2As2
• 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
• Observation of Fermi-surface-dependent nodeless superconducting gaps in Ba0.6K0.4Fe2As2
• The superconductivity at 18 K in LiFeAs system
• Density functional study of FeS, FeSe and FeTe: Electronic structure, magnetism, phonons and superconductivity
• Is LaO${}_{1-x}$F${}_x$FeAs an electron-phonon superconductor ?
• Pairing Symmetry in a Two-Orbital Exchange Coupling Model of Oxypnictides
• Multiband magnetism and superconductivity in Fe-based compounds
• Evolution of superconductivity in Fe-based systems with doping
• Origin of Gap Anisotropy in Spin Fluctuation Models of the Fe-pnictides
• Evolution of symmetry and structure of the gap in Fe-based superconductors with doping and interactions
• Gap Symmetry in KFe_2As_2 and cos 4θgap component in LiFeAs
• Electronic and magnetic structures of ternary iron selenides AFe${}_2$Se${}_2$ (A=K, Cs, or Tl)
• Spin fluctuations and unconventional pairing in KFe${}_2$As${}_2$
• Comment on "Quantum Criticality and Nodal Superconductivity in the FeAs-Based Superconductor KFe${}_2$As${}_2$"
• Inter-layer Superconducting Pairing Induced c-axis Nodal Lines in Iron-based Superconductors

Cited by in corpus (7)

• Extraordinary quasiparticle scattering and bandwidth-control by dopants in iron-based superconductors
• Fermi-surface topological phase transition and horizontal order-parameter nodes in CaFe${}_2$As${}_2$ under pressure
• Structural, electronic, and dynamical properties of the tetragonal and collapsed tetragonal phases of KFe${}_2$As${}_2$
• Synthesis, Structural, and Transport Properties of Cr-doped BaTi_2As_2O
• Evidence the ferromagnetic order on CoSb layer of LaCoSb${}_2$
• Pairing symmetry in monolayer of orthorhombic CoSb
• Electronic properties and surface states of RbNi${}_2$Se${}_2$