REBCO Magnet Supply
High-field operation at 16.84 T depends on REBCO high-temperature superconductor, the single most constrained item in the build.
Why REBCO
Reaching 16.84 T peak field in a compact spherical tokamak requires high-temperature superconductor. REBCO (rare-earth barium copper oxide) tape carries the current density needed at high field and elevated temperature margin, which is why it anchors the magnet design and the schedule.
The supply constraint
REBCO tape is manufactured by a limited set of producers, and the quantity and quality needed for a full toroidal-field magnet set are substantial. Conductor procurement is therefore a long-lead commitment placed at the start of construction, and conductor qualification, verifying current-carrying performance and defect rates, is part of accepting the supply.
From tape to magnet
- Procure and qualify conductor tape against current-density and defect criteria
- Wind and insulate coils to hold tolerance under high field
- Assemble the structural casing that carries Lorentz loads
- Integrate quench protection to keep the magnet within temperature margin
Where it is proven
The magnet is proven at gate G2: the coil set must reach and hold 16.84 T peak with 8 T on axis under operational load. REBCO supply quality feeds directly into whether G2 passes, which is why conductor qualification is treated as rigorously as the field test itself.
The magnet is a design informed by REBCO practice; the specific coil set is not yet built. Author reconciliation on some REBCO material details is tracked as an open item in the program's documentation.