Quantum oscillations in the parent magnetic phase of an iron arsenide high temperature superconductor

TL;DR

This study uses quantum oscillation measurements to explore the Fermi surface and electronic properties of SrFe2As2, an antiferromagnetic parent compound of iron-arsenide superconductors, revealing Fermi liquid behavior and spin-density wave features.

Contribution

It provides the first detailed quantum oscillation data on the parent magnetic phase of an iron-arsenide superconductor, linking Fermi surface properties to high Tc superconductivity.

Findings

Fermi liquid behavior observed in quantum oscillations

Small Fermi surface pockets consistent with spin-density wave formation

Superconductivity can emerge from a metallic spin-density wave state

Abstract

We report quantum oscillation measurements in SrFe2As2 - which is an antiferromagnetic parent of the iron-arsenide family of superconductors - known to become superconducting under doping and the application of pressure. The magnetic field and temperature dependences of the oscillations between 20 and 55 T in the liquid helium temperature range suggest that the electronic excitations are those of a Fermi liquid. We show that the observed Fermi surface comprising small pockets is consistent with the formation of a spin-density wave. Our measurements thus demonstrate that high Tc superconductivity can occur on doping or pressurizing a conventional metallic spin-density wave state.