The Influence of Neutron Irradiation on (B0.65C0.35)Ba1.4Sr0.6Ca2Cu3Oz Superconducting Phase: the Role of the Grain Edge

TL;DR

This study investigates how neutron irradiation affects the superconducting properties of (B0.65C0.35)Ba1.4Sr0.6Ca2Cu3Oz, revealing changes in critical temperature, resistivity, and critical current density, with a focus on grain edge effects.

Contribution

It provides new insights into the role of neutron irradiation on grain edge phenomena and surface barriers in this superconductor, linking microscopic effects to macroscopic properties.

Findings

Neutron irradiation decreases critical temperature and transport critical current density.

It increases residual and normal state resistivity.

Intragranular critical current density improves after irradiation.

Abstract

Using the transport and magnetization measurements the influence of neutron irradiation at a fluence of 5x10$^{17}$ n cm$^{-2}$ on (B0.65C0.35)Ba1.4Sr0.6Ca2Cu3Oz has been investigated. The neutron irradiation was found to decrease critical temperature and transport critical current density, increase the residual and normal state resistivity, and improve the intragranular critical current density with 1.6x10$^{57}$ A/cm$^{2}$ (at 77.3K and in the applied field up to 160 kA m) and \Delta Mirr/\Delta Mnonirr ratio (up to factor of 3) at highest field used for investigation. The field dependence of this ratio, which is below the unity at very low field but higher than 1 at high fields, correlated with the shape of the hystertic loops as well as with the change of the transport parameters after irradiation suggests the role of the irradiation induced effects on the grain edges. We discuss these effects in the framework of the Bean-Livingstone surface barriers and geometrical barriers.