[2L08-12] Structural Materials for Nuclear Fusion Reactors 1

[2L10] Irradiation effects on high entropy cuprate superconductor thin films

*Kota Sakurai¹, Naoko Oono¹, Aichi Yamashita², Mahiro Yamanaka², Yoshikazu Mizuguchi², Kiyohiro Yabuuchi³ (1. Yokohama Natl. Univ., 2. Tokyo Metropolitan Univ., 3. Kyoto Univ.)

Keywords:high entropy, superconducting magnet, irradiation defect

Copper oxide superconductor (REBCO) is a good candidate for magnets in fusion reactors. However, its superconductivity can be degraded by neutron irradiation. In order to reduce the degradation, we have applied the concept of high-entropy (HE) alloys to the RE sites of REBCO, since HE have been reported to be resistant to irradiation in recent years. In this study, single-crystal YBCO and REBCO (where the RE sites are substituted with several elements) deposited on a SrTiO₃ substrate were irradiated with 1 MeV He ions at a fluence of 4.36x10¹⁵ ions/cm². Our REBCO suppressed the decrease of T_c by 10 K compared to YBCO, while much larger decreases of Jc. The relationship between these changes and irradiation defects is discussed.