Publication Date

2-2-2021

Department

Ames Laboratory; Physics and Astronomy

Campus Units

Ames Laboratory, Physics and Astronomy

OSTI ID+

1764371

Report Number

IS-J 10408

DOI

10.1088/1361-6668/abda5d

Journal Title

Superconductor Science and Technology

Volume Number

34

Issue Number

3

First Page

035013

Abstract

We demonstrate that the anisotropy in the critical current densities, Jc, of CaK(Fe1−xNix)4As4 (x = 0, 0.015, 0.025, and 0.030) single crystals reduces with increasing chemical and irradiation-induced disorder. The magnetic field dependences of Jc are analyzed by performing magnetization measurements with H applied parallel and perpendicular to the crystallographic c-axis. The results show that undoped crystals display large anisotropies in Jc due to an enhancement of the vortex pinning with H applied parallel to the crystallographic ab-planes. This anisotropy reduces substantially as Ni addition increases. Moreover, we found that random disorder introduced by proton irradiation enhances mainly the vortex pinning for H parallel to the c-axis. Consequently, using adequate fluencies, the vortex pinning at low temperatures in both undoped and doped samples becomes close to isotropic. These results make the CaKFe4As4 system promising for applications that require isotropic Jc under magnetic fields.

DOE Contract Number(s)

AC02-07CH11358

Language

en

Publisher

Iowa State University Digital Repository, Ames IA (United States)

Available for download on Wednesday, February 02, 2022

Share

COinS