Under the right conditions, superconducting magnets allow electricity to flow essentially undisturbed, producing intense magnetic fields for a variety of uses, including nuclear fusion experiments. Naturally, a larger magnetic field gives scientists more room to explore—something that may soon be available to physicists in China, thanks to the creation of a record-setting superconducting magnet.
In a September 28 statement, the Institute of Plasma Physics at the Chinese Academy of Sciences (CAS) announced that it had developed an all-superconducting magnet. This magnet successfully generated a record-breaking magnetic field with a strength of 35.1 tesla, which is 700,000 times stronger than the Earth’s natural magnetic field. The field held for about 30 minutes, the statement said.
The previous record, which achieved 32.35 tesla, was also set by the CAS, but by a different division, the Institute of Electrical Engineering.
Chinese scientists announced on Sunday that they have successfully generated a steady magnetic field of 351,000 gauss—over 700,000 times stronger than Earth’s geomagnetic field—with a fully superconducting magnet, setting a new world record and significantly advancing the… pic.twitter.com/gFR1WQRWIH — People's Daily, China (@PDChina) September 29, 2025
“This validated the reliability of the technical solution and provided an important platform for conducting various sample experiments under 35.1 tesla conditions in a fully superconducting magnet,” said the CAS.
Hot and cold
Achieving superconducting conditions often requires extremely low temperatures. To be clear, superconducting magnets are already being used for a variety of applications, such as in MRI scanners or particle accelerators. These uses have their own fabrication complications to deal with, but for fusion applications, the low-temperature requirement makes things even trickier.
Nuclear fusion—colliding two light atoms to generate massive amounts of energy—naturally produces a lot of heat. That heat also transfers to the superconducting magnets, which are designed to safely confine the fusion reaction.
A magnet sandwich
And so, in designing these parts, engineers need to be aware of the environmental conditions the magnet will face. The new magnet is still far from being inserted into a fusion reactor, but the researchers are aware of the challenges this could pose when trying to ramp up the magnetic field’s strength, as they noted in an interview with CGTN.
The magnet’s design hints at a nice balance. It “adopts high-temperature superconducting insert-coil technology, coaxially nested with low-temperature superconducting magnets,” Liu Fang, a researcher at CAS, told CGTN.
The CAS Institute of Plasma Physics spearheads the country’s participation in the International Thermonuclear Experimental Reactor (ITER), a global collaboration set to build the world’s largest fusion reactor. The CAS has not specified whether the new magnet will directly go to ITER, although it noted that it had been tasked with providing many parts of the reactor, including superconducting technology.