Magneto-elastically coupled structural, magnetic and superconducting order parameters in BaFe$_{2}$(As$_{1-x}$P$_{x}$)$_{2}$

TL;DR

This study investigates how mechanical strain affects the magnetic and superconducting properties of BaFe$_{2}$(As$_{1-x}$P$_{x}$)$_{2}$, highlighting the strong magneto-elastic coupling in these iron-based superconductors.

Contribution

It provides direct experimental evidence of the magneto-elastic coupling influencing magnetic and superconducting transitions in BaFe$_{2}$(As$_{1-x}$P$_{x}$)$_{2}$.

Findings

Néel transition is highly sensitive to stress, especially near optimal doping.

Superconducting transition temperature changes significantly with applied strain.

Magneto-elastic coupling plays a crucial role in the phase behavior of the material.

Abstract

We measure the transport properties of mechanically strained single crystals of BaFe$_{2}$(As$_{1-x}$P$_{x}$)$_{2}$ over a wide range of $x$. The N\'eel transition is extremely sensitive to stress and this sensitivity increases as optimal doping is approached, even though the transition itself is strongly suppressed. Furthermore, we observe significant changes in the superconducting transition temperature with applied strain, which mirror changes as a function of the composition $x$. These experiments are a direct illustration of the intimate coupling between different degrees of freedom in iron-based superconductors, revealing the importance of magneto-elastic coupling to the magnetic and superconducting transition temperatures.