One of the scientific teams helping to develop a Chinese nuclear fusion reactor capable of producing unlimited power has unveiled a device they say will be key to testing whether the facility can withstand the intense flows of plasma produced during fusion.
Chi Xiao, or “Crimson Skyblade”, is a superconducting linear plasma device that is intended to help scientists test building materials for use in a fusion reactor, according to a panel of experts who introduced the device on Tuesday.
Experiments are under way at the Hefei-based Experimental Advanced Superconducting Tokamak (EAST) facility to mimic the sun’s fusion reactions to produce light and heat.
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But building a nuclear fusion reactor is a formidable challenge that will require fortified walls made of special materials that can survive out-of-this-world conditions.
“Developing wall materials that are both resilient and resistant to damage is extremely difficult. To test such materials, we need advanced simulation environments,” said project leader Professor Zhou Haishan, with the Hefei Institutes of Physical Science, at the Chinese Academy of Sciences.
His team spent more than five years developing the powerful linear plasma device. At a length of 15.5 metres (51 feet) and a weight of about 22.5 tonnes, it features a streamlined structure resembling a sword, and can continuously generate plasma that is propelled at high speeds using magnetic fields.

“This device can eject ... the equivalent [of] billions of billions of millions of particles. It can operate continuously for more than 24 hours,” Zhou said.
Chi Xiao, draws inspiration from a legendary Chinese sword associated with Emperor Gaozu, founder of the Han dynasty, who reigned from 202 to 195BC.
“Chi”, or bright red, symbolises auspiciousness and authority, while “Xiao” represents the vastness of the sky, reflecting the grandeur and limitless potential of the device.
Professor Ye Minyou, head of the review panel, and a professor at the University of Science and Technology of China, said China was now the second country after the Netherlands to have such a device, with Crimson Skyblade surpassing the performance of its predecessor.
China’s strides in nuclear fusion have positioned it as a world leader in some areas, due in large part to its rapid pace of development. According to an article in the journal Nature in August last year, China’s annual investment in nuclear fusion research was estimated to reach US$1.5 billion – nearly twice the amount of annual US government funding in the field.

China is at the forefront of nuclear fusion research, playing an essential role in the International Thermonuclear Experimental Reactor project, the world’s largest fusion reactor now under construction in France.
Plans are also in place for the domestically developed China Fusion Engineering Test Reactor, which will produce a massive quantity of heat with a peak power output of up to 2 gigawatts.
The project is expected to be online for large-scale scientific experiments by 2035, with commercial use targeted for 2050.
“Crimson Skyblade will provide critical support for China’s next-generation ‘artificial sun’ project. Not only will the device serve Chinese scientists, but it will also facilitate international cooperative research, which will be open to global contributions,” state news agency Xinhua reported.
More from South China Morning Post:
- Breakthrough in China’s artificial sun project could lead to more stable fusion energy: international team
- China launches ‘Kuafu’ nuclear fusion research facility, named after mythical giant, in quest to build ‘artificial sun’
- China’s ‘artificial sun’ hits new high in clean energy boost
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