China’s fully superconducting tokamak, the first in the world with a non-circular cross-section, and holder of multiple long-pulse plasma duration records.
EAST (Experimental Advanced Superconducting Tokamak), originally designated HT-7U, is a fully superconducting tokamak operated by the Institute of Plasma Physics of the Chinese Academy of Sciences (ASIPP) in Hefei, Anhui Province, China. When it achieved first plasma in September 2006, EAST became the first tokamak in the world to combine fully superconducting toroidal-field and poloidal-field coil systems with a non-circular (D-shaped) plasma cross-section—a combination essential for any future steady-state fusion reactor.[1]
EAST uses 16 NbTi superconducting toroidal-field coils and a set of superconducting poloidal-field coils, all cooled by supercritical helium to approximately 4.5 K. The fully superconducting coil system eliminates the resistive power losses that limit pulse length in copper-coil tokamaks, making EAST purpose-built for long-pulse and ultimately steady-state operation. The device has an ITER-like single-null divertor configuration and a high-vacuum vessel with actively cooled plasma-facing components, including a combination of carbon and tungsten/molybdenum materials that has evolved through successive upgrades.[3]
A diverse heating and current-drive suite provides approximately 28 MW through lower-hybrid current drive (LHCD), ion cyclotron resonance heating (ICRH), electron cyclotron resonance heating (ECRH), and neutral beam injection (NBI). The lower-hybrid system has been particularly central to EAST’s long-pulse mission, providing efficient non-inductive current drive.
EAST’s defining contribution to fusion research has been the systematic extension of plasma pulse duration. In 2017, EAST reported maintaining H-mode plasma for over 100 seconds—at the time a record for superconducting tokamaks.[2] Subsequent campaigns pushed these durations considerably further: in 2023, EAST reported achieving a high-confinement (H-mode) plasma sustained for 403 seconds at electron temperatures of approximately 70 million °C, and a total plasma duration exceeding 1,000 seconds in a lower-confinement steady-state scenario. These results, while reported by ASIPP and covered in the international press, should be understood as claimed records pending independent peer-reviewed publication of the full dataset.
EAST has also contributed to research on divertor heat-flux management, real-time plasma control, and the integration of multiple heating and current-drive systems—all areas critical to ITER and to the design of China’s planned next-step device, CFETR (China Fusion Engineering Test Reactor).[2]
As of 2026, EAST remains in active operation with ongoing upgrades to its heating systems, divertor, and diagnostics. It serves as a principal testbed for steady-state fusion operation and as a technology and training platform for CFETR. EAST’s results are also contributed to the international ITER research program.[1]