Electronic phase diagram of disordered Co doped BaFe2As2

TL;DR

This study maps the electronic phase diagram of disordered Co-doped BaFe2As2 thin films, revealing how disorder shifts the superconducting dome and allows higher transition temperatures in underdoped regimes.

Contribution

It provides new insights into how disorder affects the superconducting phase diagram in iron pnictides, especially in thin film form, differing from single crystal behavior.

Findings

Superconducting dome shifts to lower doping in disordered thin films.

Superconducting transition temperatures above 27 K are achievable in underdoped regimes.

Disorder significantly alters the phase diagram compared to single crystals.

Abstract

Superconducting and normal state transport properties in iron pnictides are sensitive to disorder and impurity scattering. By investigation of Ba(Fe1-xCox)2As2 thin films with varying Co concentration, we demonstrate that in the dirty limit the superconducting dome in the electronic phase diagram of Ba(Fe1-xCox)2As2 shifts towards lower doping concentrations, which differs significantly from observations in single crystals. We show that especially in the underdoped regime superconducting transition temperatures higher than 27 K are possible.