Antiferromagnetic order and spin dynamics in iron-based superconductors

TL;DR

This review discusses how neutron scattering studies reveal the evolution of spin excitations in iron-based superconductors and their connection to high-temperature superconductivity, comparing them with other unconventional superconductors.

Contribution

It provides a comprehensive overview of neutron scattering results on iron-based superconductors, highlighting the role of spin dynamics and their evolution with doping and substitution.

Findings

Spin excitation spectra evolve with doping and substitution.

Common features of spin excitations across different superconductor families.

Relationship between spin dynamics and superconductivity discussed.

Abstract

High-transition temperature (high-$T_c$) superconductivity in the iron pnictides/chalcogenides emerges from the suppression of the static antiferromagnetic order in their parent compounds, similar to copper oxides superconductors. This raises a fundamental question concerning the role of magnetism in the superconductivity of these materials. Neutron scattering, a powerful probe to study the magnetic order and spin dynamics, plays an essential role in determining the relationship between magnetism and superconductivity in high-$T_c$ superconductors. The rapid development of modern neutron time-of-flight spectrometers allows a direct determination of the spin dynamical properties of iron-based superconductors throughout the entire Brillouin zone. In this review, we present an overview of the neutron scattering results on iron-based superconductors, focusing on the evolution of spin excitation spectra as a function of electron/hole-doping and isoelectronic substitution. We compare spin dynamical properties of iron-based superconductors with those of copper oxide and heavy fermion superconductors, and discuss the common features of spin excitations in these three families of unconventional superconductors and their relationship with superconductivity.