Iron based superconductors: magnetism, superconductivity and electronic structure

TL;DR

This paper reviews the electronic structure of iron-based superconductors, emphasizing how ARPES studies reveal their complex multi-band features and the interplay of magnetism and superconductivity.

Contribution

It provides a comprehensive overview of ARPES findings on FeSC electronic structures and discusses how these insights relate to magnetic and superconducting properties.

Findings

Electronic structure determined by ARPES aligns with band calculations.

Small differences in electronic structure may explain magnetic and pairing mechanisms.

Complex multi-band features are key to understanding FeSC physics.

Abstract

Angle resolved photoemission spectroscopy (ARPES) reveals the features of the electronic structure of quasi-two-dimensional crystals, which are crucial for the formation of spin and charge ordering and determine the mechanisms of electron-electron interaction, including the superconducting pairing. The newly discovered iron based superconductors (FeSC) promise interesting physics that stems, on one hand, from a coexistence of superconductivity and magnetism and, on the other hand, from complex multi-band electronic structure. In this review I want to give a simple introduction to the FeSC physics, and to advocate an opinion that all the complexity of FeSC properties is encapsulated in their electronic structure. For many compounds, this structure was determined in numerous ARPES experiments and agrees reasonably well with the results of band structure calculations. Nevertheless, the existing small differences may help to understand the mechanisms of the magnetic ordering and superconducting pairing in FeSC.