Effect of uniaxial pressure on the magneto-structural transitions of iron arsenide superconductors

TL;DR

This paper presents a theoretical study on how uniaxial pressure affects the magnetic and structural transition temperatures in iron arsenide superconductors, linking these changes to magneto-elastic interactions.

Contribution

It introduces a simple magneto-elastic model explaining the variation of transition temperatures under uniaxial stress in iron arsenide superconductors.

Findings

Transition temperatures increase with uniaxial stress.

Antiferromagnetic bonds are longer than ferromagnetic ones in the magnetic phase.

Model predictions can be experimentally tested.

Abstract

We study theoretically the variation of the magnetic and the structural transition temperatures of the iron arsenide superconductors with external uniaxial stress. We show that the increase of the transition temperatures reported in recent experiments is compatible with a simple magneto-elastic model in which the physical origin of this variation is linked to the fact that antiferromagnetic bonds are longer than the ferromagnetic ones in the magnetic phase. We make predictions which can be verified in order to test the relevance of this model.