Activation of high- Tc superconductors due to neutron irradiation

Abstract

For actual application of high- T c superconductors (HTSC), the improvement of J c is required. It has been reported that pinning centers in the HTSC increase J c. Particle beam irradiation is one of the most effective methods to introduce strong pinning centers into HTSC for J c enhancement. In particular, neutron irradiation is very effective for bulk materials, although the activation might be an important problem. In this study, activation of HTSCs was analysed by using the computer code, ORIGEN-II. The contribution of impurities in Bi 2Sr 2CaCu 2O 8+ x (Bi-2212) to 1 cm dose equivalent occupies about 15%. In RE-123 family, Y, La, Nd, Sm. Gd, Dy, Ho and Yb gave low activation. In the case of U-doped Y-123, about 75% of the activity is from the contribution of the fission products.