Tailoring the Superconductivity and Antiferromagnetic Order in SrFe2-xRhxAs2

TL;DR

This study investigates how Rh doping in SrFe2As2 induces superconductivity by suppressing antiferromagnetic order, revealing a maximum Tc of 22 K at x=0.25, and suggesting superconductivity is linked to AF suppression.

Contribution

It demonstrates that Rh doping suppresses AF order and induces superconductivity in SrFe2As2, providing a phase diagram similar to Co doping and highlighting the AF suppression as key to superconductivity.

Findings

Maximum Tc of 22 K at x=0.25 Rh doping

Resistivity anomaly shifts with doping level

Superconductivity linked to AF order suppression

Abstract

By doping Rh to the Fe sites in SrFe2As2, superconductivity is induced when the antiferromagnetic (AF) order is suppressed. The maximum superconducting transition temperature was found at about 22 K with the doping level of x = 0.25. It is found that the resistivity anomaly associating with the AF order reveals a sharp drop for the parent phase and the samples with low doping (x = 0.05), while it evolves into an uprising at a higher doping level (x = 0.1). A general phase diagram is depicted which exhibits the similarity with that of Co doping. Regarding the close maximum superconducting transition temperatures in doping Co, Rh and Ir, we argue that the superconductivity is intimately related to the suppression of the AF order, rather than the electron-phonon coupling.