A linear plasma generator developed by Chinese scientists has achieved its design specifications, positioning China as the second country in the world, following the Netherlands, to develop such a high-flux plasma generator. The Hefei Institutes of Physical Science (HFIPS) of the Chinese Academy of Sciences announced this achievement on Tuesday.

This device provides a vital tool for developing key materials for the "artificial sun," a fusion facility designed to harness clean and sustainable energy

Named the Superconducting Plasma Wall Interaction Linear Device (SWORD), the generator features a streamlined design inspired by Chixiao, a legendary sword from ancient Chinese lore. Measuring 15.5 meters in length and weighing approximately 22.5 tonnes, SWORD is capable of generating an impressive flux of 10²⁴ particles per square meter per second and can operate continuously for over 24 hours.

An expert panel evaluated SWORD's performance on Tuesday, confirming that the device has successfully met its design specifications.

This advancement enables rigorous testing of plasma-facing materials, which are critical for fusion devices designed to replicate the sun's nuclear fusion processes. By utilizing abundant resources found in seawater, these devices aim to generate clean energy.

Since the mid-20th century, scientists have focused on developing experimental devices for controlled nuclear fusion—often referred to as "artificial suns"—that mimic the nuclear fusion mechanisms inherent in the sun.

However, one of the most significant challenges in their development has been the creation of durable materials capable of withstanding the intense bombardment from high-energy plasma particles on reactor walls.

"For the 'artificial sun' to generate electricity continuously for extended periods, it is crucial to develop materials capable of enduring the extreme conditions within the reactor. This requires a highly advanced experimental environment to test plasma-facing materials," said ZHOU Haishan, a researcher at Institute of Plasma Physics (ASIPP), HFIPS.

ASIPP is also home to Experimental Advanced Superconducting Tokamak.

ZHOU noted that it took the team more than five years to overcome significant technical challenges in developing SWORD.

The successful development of this device is expected to support research on China's next-generation experimental fusion reactors. The device will also be available for international collaboration, according to ZHOU.

A linear plasma generator developed by China has reached its design specifications to develop such a high-flux plasma generator.  (Image by YE Hualong)