Dependences of HTS tape critical parameters on fluences under irradiation with heavy ions and high energy electrons

Abstract

Experimental data on the study of modifications of two types of the YBCO(123)-based composite tape under irradiation with electrons with the energy of 23 MeV and 132 Xe 27+ (167 MeV), 84 Kr 17+ (107 MeV), and 40 Ar 8+ (48 MeV) ions in a wide range of irradiation doses are presented. It is shown that no changes in the HTS transition temperature and critical current occurred under electron irradiation up to the dose D ≈ 10 −4 disp/a (displacements per atom). The threshold dose of irradiation with 132 Xe 27+ ions, at which superconductivity disappears, is determined. In comparison with the initial value, the critical current of 40 Ar 8+ ions is found to increase by ≈18% in the zero magnetic field at T = 77 K. This effect can be explained by the pinning centers for Abrikosov vortices induced by relatively small ion irradiation doses. High doses of heavy ions lead to partial or complete amorphization of a superconductor, which results first in a decrease in the critical current and transition temperature and then in a total disappearance of superconductivity. X-ray diffraction is used to study the changes in the crystal structure of the YBCO(123) superconductor under ion irradiation.