Status of Iron Based Superconductors: characteristics and relevant properties for applications

TL;DR

This paper reviews the development and key properties of iron-based superconductors over 18 years, highlighting their similarities to cuprates, unique multiband features, and potential for quantum computing applications.

Contribution

It provides a comprehensive overview of IBS research, focusing on their characteristics, strategies to enhance transition temperature, and critical current density.

Findings

IBSs share similarities with cuprates, such as antiferromagnetic parent compounds.

Distinct features include multiband superconductivity and extended s-wave symmetry.

Some IBSs are topological superconductors suitable for quantum computing.

Abstract

Since the discovery of iron-based superconductors (IBSs) on LaFePO in 2006, many types of IBSs have been fabricated. IBSs have usually been compared to cuprates and MgB2, and the methodology of research developed by them have been implemented to IBSs. As a result, many similarities between IBSs and cuprates have been revealed, e.g., the parent compounds being antiferromagnets and grain boundaries being weak-links to some extent. On the other hands, the distinct features of IBSs are highlighted as multiband superconductors (i.e., the 5 bands of Fe 3d orbital crossing Fermi level) and extended s-wave symmetry. Additionally, some of the IBSs are topological superconductors that can be possible platforms for quantum computing. In this paper, an overview of IBS research and development in the last 18 years will be reported, involving characteristics of IBSs as well as strategies of increasing the superconducting transition temperature and critical current density.