Neutron irradiation of coated conductors

TL;DR

This study investigates how neutron irradiation introduces defects in coated conductors, reducing anisotropy and affecting critical current density, with implications for optimizing superconductor performance.

Contribution

It provides new insights into the effects of neutron-induced defects on the critical current and anisotropy in coated conductors, highlighting differences between optimized and non-optimized tapes.

Findings

Neutron irradiation reduces Jc anisotropy.

Irradiation enhances the irreversibility line in non-optimized tapes.

Defects do not improve performance in state-of-the-art conductors.

Abstract

Various commercial coated conductors were irradiated with fast neutrons in order to introduce randomly distributed, uncorrelated defects which increase the critical current density, Jc, in a wide temperature and field range. The Jc-anisotropy is significantly reduced and the angular dependence of Jc does not obey the anisotropic scaling approach. These defects enhance the irreversibility line in not fully optimized tapes, but they do not in state-of-the-art conductors. Neutron irradiation provides a clear distinction between the low field region, where Jc is limited by the grain boundaries, and the high field region, where depinning leads to dissipation.