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

Cornelis Jacominus van Der Beek (1) , Sultan Demirdis (1) , Dorothée Colson (2) , F. Rullier-Albenque (2) , Yanina Fasano (3) , Takasada Shibauchi (4) , Yuji Matsuda (4) , Shigeru Kasahara (4, 5, 6) , Piotr Gierlowski (7) , Marcin Konczykowski (1)

1 LSI - Laboratoire des Solides Irradiés - Irradiated Solids Laboratory
2 SPEC - UMR3680 - Service de physique de l'état condensé
3 LBT - Laboratorio de Bajas Temperaturas
4 Department of Physics, Kyoto University
5 NIMS - National Institute for Materials Science
6 Research Center for Low Temperature and Materials Sciences
7 IFPAN - Instytut Fisyki

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.

Keywords: Supraconductivité; Superconductivity; Supraconductivité à base de fer; Iron-based superconductivity; Effet du désordre; Disorder effect; irradiation; courants critiques; critical current; critical temperature; surface resitance

Domains: Superconductivity [cond-mat.supr-con]

Cornelis Jacominus van Der Beek, Sultan Demirdis, Dorothée Colson, F. Rullier-Albenque, Yanina Fasano, et al.. Electron irradiation of Co, Ni, and P-doped BaFe2As2 - type iron-based superconductors. Materials and Mechanisms of Superconductivity 2012, Jul 2012, Washington DC, United States. ⟨hal-00731254v1⟩