Tight-binding models for the new iron based superconductor materials

TL;DR

This paper develops minimal tight-binding models that accurately capture the complex low-energy electronic structure of iron-based superconductors, facilitating studies of their magnetic and superconducting properties.

Contribution

It provides quantitatively accurate minimal tight-binding models for the electronic structure of iron-based superconductors, addressing their complexity despite simple crystal structures.

Findings

Bonding and orbital structures analyzed in detail.

Minimal tight-binding models accurately describe low-energy electronic states.

Models enable better understanding of magnetic and superconducting instabilities.

Abstract

The rich novel materials class of iron based superconductors turned out to exhibit a very complex electronic structure, despite of the simplicity of their crystal structures. For various approaches to study the instability against magnetic order or superconductivity, a real space description of the electronic structure is required. Here, the bonding situation and the orbital structure of the electronic state are analyzed and minimum tight-binding models quantitatively correctly describing the low-energy electronic structure are provided.