KSTAR — the Korea Superconducting Tokamak Advanced Research device in Daejeon — is South Korea's flagship fusion experiment and a leader in sustaining very hot plasmas for long durations.
Operated by the Korea Institute of Fusion Energy and producing first plasma in 2008, KSTAR was among the first tokamaks built with fully superconducting magnets, and the first to use niobium-tin — the same conductor chosen for 📝ITER's largest coils — in a 📝Tokamak magnet system. Its research program concentrates on a specific frontier: holding a 📝plasma at ion temperatures above 100 million degrees Celsius — the operating range of a 📝fusion power plant — for progressively longer intervals, reaching 48 seconds in its 2024 campaign alongside high-confinement operation sustained for over 100 seconds.
The near-neighbor comparison is 📝EAST, China's superconducting tokamak: EAST holds the records for total 📝pulse length, with discharges beyond 1,000 seconds, while KSTAR has pushed how long a plasma stays in the hottest, most reactor-relevant range. The two machines, along with superconducting successors elsewhere, form the empirical bridge between short-pulse copper-magnet experiments and the continuously operating plants fusion ultimately requires. KSTAR's recent upgrade to a 📝tungsten 📝divertor — replacing carbon plasma-facing surfaces with the material chosen for ITER and most power-plant designs — extends that rehearsal to the exhaust problem, testing how reactor materials withstand sustained heat flux.