KRONOS·FUSION
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Comparison

HTS vs LTS Magnets

High-temperature superconductors reach far higher fields and warmer temperatures than low-temperature ones — the difference that makes compact high-field fusion possible.

HTS (REBCO)
Higher field (24.6 T), ~20 K, demountable
LTS (Nb₃Sn/NbTi)
Capped ~12–20 T, ~4 K, welded
Kronos
HTS / REBCO
Consequence
HTS enables compact high-field designs

The magnet is the enabling technology of compact fusion, and the choice between high-temperature (HTS) and low-temperature (LTS) superconductor is decisive. LTS materials like Nb₃Sn and NbTi are mature but cap out around 12–20 T and must run near 4 K in a welded, permanent coil. HTS tape (REBCO) keeps superconducting at much higher fields and warmer temperatures.

PropertyHTS (REBCO) / LTS (Nb₃Sn/NbTi)
Peak field24.6 T (Kronos) / ~12–20 T
Operating temperature~20 K / ~4 K
ServiceabilityDemountable joints possible / welded, permanent
EnablesCompact high-field tokamaks / larger, lower-field machines

Because power density scales with the fourth power of field, the higher field HTS enables is what shrinks the machine — the entire premise of the Kronos 24.6 T magnet system.