China's next-generation "artificial sun" at the Southwestern Institute of Physics in Chengdu, designed to push plasma current and temperature boundaries in support of ITER and future Chinese fusion reactors.
The HL-2M Tokamak, operated by the Southwestern Institute of Physics (SWIP) in Chengdu, Sichuan Province, is China's largest and most advanced magnetic-confinement fusion research device. Often called China's "artificial sun" in domestic media, it achieved first plasma on 4 December 2020, marking a significant milestone in the country's ambitious fusion energy program.1
HL-2M is a conventional-aspect-ratio tokamak with a major radius of approximately 1.78 m and a minor radius of 0.65 m. The device was designed to achieve plasma currents of up to 2.5 MA and ion temperatures exceeding 150 million degrees Celsius—roughly ten times hotter than the core of the Sun. Its toroidal magnetic field reaches approximately 2.2 T at the plasma center.2
The machine features a flexible divertor configuration, advanced plasma-control systems, and powerful auxiliary heating that includes neutral beam injection (NBI) and electron cyclotron resonance heating (ECRH). Its design allows researchers to study high-performance plasma scenarios, including high-beta operation and advanced plasma shaping, that are directly relevant to ITER and the proposed Chinese Fusion Engineering Test Reactor (CFETR).3
HL-2M serves as a critical platform in China's two-pronged fusion strategy: contributing to the international ITER project while simultaneously developing indigenous expertise for CFETR. The machine is tasked with investigating high-confinement (H-mode) plasma regimes, edge-localized mode (ELM) control, and disruption mitigation—all essential physics challenges for burning-plasma devices.2
Its predecessor, HL-2A, operated from 2002 and achieved notable results in plasma instability research. HL-2M represents a major step up in capability, with roughly triple the plasma current and significantly enhanced heating power, enabling access to reactor-relevant plasma conditions in a mid-scale device.
China's fusion program has expanded rapidly since the early 2000s. Alongside HL-2M, the EAST tokamak at the Hefei Institutes of Physical Science pursues long-pulse superconducting operation, while the J-TEXT tokamak at Huazhong University focuses on disruption physics. Together, these facilities form a complementary research ecosystem.4
Since first plasma, HL-2M has conducted multiple experimental campaigns, progressively increasing plasma current and exploring advanced divertor configurations. The device has also served as a testbed for plasma diagnostics and control systems intended for deployment on larger machines. Its operational flexibility makes it a valuable contributor to the global fusion research portfolio, alongside comparable mid-scale tokamaks such as KSTAR, WEST, and MAST Upgrade.5