Development of RE-Ba-Cu-O superconductors in the U.S. for ultra-high field magnets

Abstract High-temperature superconductors (HTSs) make it possible to achieve magnetic fields beyond the 23.5 T limit of low-temperature superconductors. For higher energy density, high-performance HTS with J e > 1000 A mm −2 enables reduction in coil winding length and a smaller magnet size. Among HTS, REBa 2 Cu 3 O 7− δ (REBCO, RE = rare earth) exhibits excellent mechanical properties and superior performance over a wide range of temperatures and magnetic fields. REBCO tapes can be converted to various formats, including round wires. The state-of-the-art REBCO superconductors for ultra-high field magnets, including cable/wire architectures, are reviewed. R&D needs to address the remaining challenges with REBCO superconductors for ultra-high magnetic field applications is discussed.