On superconducting and magnetic properties of iron-oxypnictides

TL;DR

This paper explores the pairing symmetry and magnetic properties of iron-oxypnictides, a class of high-temperature superconductors, analyzing how their electronic structure influences superconducting and magnetic states.

Contribution

It investigates the possible pairing symmetries and magnetic orders in iron-oxypnictides, highlighting the role of Fermi surface topology and excitonic effects in their superconducting behavior.

Findings

Multiple Fermi pockets influence pairing symmetry.

Antiferromagnetic order may coexist with superconductivity.

Doping affects the transition temperature Tc.

Abstract

Pairing symmetry in oxypnictides, a new family of multiband high-Tc superconductors, is partially imposed by the positions of multiple Fermi pockets, which itself can give rise to new order parameters, such as s+,- states or the state of dx^2-y^2 symmetry. Other pairing states may appear on small pockets for long range interactions, but they are expected to be sensitive to defects. We identify the competing antiferromagnetic order with the triplet exciton transition in the semi- metallic background and discuss whether its coexistence with superconductivity explains the doping dependence of Tc.