High temperature Superconductors (HTS) show the ability to conduct high current density even under high magnetic field making them well suited to develop very high field magnets. Two studies related to HTS for high field magnets will be introduced.
The first study falls in the framework of the development of the 33 T cryogen-free all-superconducting magnet (CSM) under development at Tohoku University, Japan [1]. A large-scale prototype of the future HTS insert was extensively tested. This presentation will introduce these measurements related to assessment of the magnetic field quality [2], method of protection, evaluation of mechanical strain and stability.
The second study addresses the limited data of Ic magnetic field dependence in the very high field region while developing magnets in this range of operation. At the University of Tokyo, we combined pulsed magnetic field to access the very high field region and fast Ic current measurement to determine Ic over full-width HTS tape. A dedicated probe with sufficient voltage accuracy was developed. It could make it possible to access Ic over full-width HTS tape under 39 T [3].
[1] S. Awaji et al., “Progress of 33 T Cryogen-Free Superconducting Magnet Project at HFLSM,” in IEEE TAS 35 4300406 (2025)
[2]A. Zampa et al., “Effects on the Magnetic Field Stability of Coupling Currents Existing in a Two-Tape Bundle of a HTS Insert Prototype,” in IEE TAS 35 4300206 (2025)
[3] A. Zampa, Y. Tsuchiya, A. Matsuo, K. Kindo, K. Mizuno and Y. Kohama, “Critical Current Measurement Over Full-Width HTS Tapes Under Flat-top Pulsed Magnetic Field Up to 38.7 T” in IEEE TAS 36 9001305 (2026)
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