Electron irradiation of Co, Ni, and P-doped BaFe2As2 - type iron-based superconductors

Abstract

High energy electron irradiation is used to controllably introduce atomic-scale point defects into single crystalline Ba(Fe_1-xCo_x)_2As_2, Ba(Fe_1-xNi_x)_2As_2, and BaFe_2(As_1-xP_x)_2. The appearance of the collective pinning contribution to the critical current density in BaFe_2(As_1-xP_x)_2, and the magnitude of its enhancement in Ba(Fe_1-xCo_x)_2As_2, conform with the hypothesis of quasi-particle scattering by Fe vacancies created by the irradiation. Whereas the insignificant modification of the temperature dependence of the superfluid density in Ba(Fe_1-xCo_x)_2As_2 and Ba(Fe_1-xNi_x)_2As_2 points to important native disorder present before the irradiation, the critical temperatures of these materials undergo a suppression equivalent to that observed in the much cleaner BaFe_2(As_1-xP_x)_2. This lends credence to the hypothesis of line nodes of the order parameter (at finite k_{z}) in the former two materials.

arXiv comment17 pages, soumis pour publications dans les actes de M2S-2012; Materials and Mechanisms of Superconductivity 2012, Washington DC : United States (2012)

References in corpus (4)

• Superconductivity suppression of Ba0.5K0.5Fe2-2xM2xAs2 single crystals by substitution of transition-metal (M = Mn, Ru, Co, Ni, Cu, and Zn)
• New Phase Induced by Pressure in the Iron-Arsenide Superconductor K-Ba122
• Anomalous impurity effects in the iron-based superconductor KFe${}_2$As${}_2$
• Doping-induced vertical line nodes in the superconducting gap of the iron arsenide K-Ba122 from directional thermal conductivity

Cited by in corpus (2)

• Superconducting Properties of the $s^{\pm }$-wave state: Fe-based superconductors
• Interplay between superconductivity and itinerant magnetism in underdoped Ba${}_{1-x}$K${}_x$Fe${}_2$As${}_2$ ($x=$ 0.2) probed by the response to controlled point-like disorder