Simple Real-Space Picture of Nodeless and Nodal s-wave Gap Functions in Iron Pnictide Superconductors

Abstract

We propose a simple way to parameterize the gap function in iron pnictides. The key idea is to use orbital representation, not band representation, and to assume real-space short-range pairing. Our parameterization reproduces fairly well the structure of gap function obtained in microscopic calculation. At the same time the present parameterization is simple enough to obtain an intuitive picture and to develop a phenomenological theory. We also discuss simplification of the treatment of the superconducting state.

4 pages

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Cited by in corpus (8)

• Nodes in the Gap Function of LaFePO, the Gap Function of the Fe(Se,Te) Systems, and the STM Signature of the s${}_{\pm }$ Pairing
• Spin fluctuations and unconventional pairing in KFe${}_2$As${}_2$
• Single Impurity Problem in Iron-Pnictide Superconductors
• Fermi-Suface Evolution by Transition-metal Substitution in the Iron-based Superconductor LaFeAsO
• 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
• Cooperative effects of Coulomb and electron-phonon interactions in the two-dimensional 16-band d-p model for iron-based superconductors
• Orbital-Selective Superconductivity and the Effect of Lattice Distortion in Iron-Based Superconductors
• Coexistence of Antiferromagnetism and Superconductivity in Iron-Based Superconductors