To send a particle beam where you want it to go, you need magnets that can "bend" or steer it: dipoles. These magnets are central to large particle accelerators, and experts at Berkeley Lab have repeatedly set world records for the magnetic strength, measured in teslas.

"We've been making record superconducting magnets for decades, going back to the '80s and '90s, with designs in different magnet styles," said Soren Prestemon, who heads the Berkeley Center for Magnet Technology at the lab, as well as the national U.S. Magnet Development Program that is led by the ATAP Division. "Dipoles for future colliders have been our main research arena."

Berkeley Lab scientists have led theory, modeling, and design of magnets made with niobium-tin, a high-performance superconducting material that can handle stronger magnetic fields than its predecessor (niobium-titanium). In 1997, a prototype niobium-tin dipole at Berkeley Lab shattered world records for particle-collider-style magnets, reaching 13.5 tesla. Only a few years later, Berkeley Lab broke its own record, building a 16-tesla dipole with a magnetic field more than 300,000 times as strong as the Earth's.

Now researchers are advancing dipoles made of high-temperature superconductors (HTS), which can work at warmer (though still very cold) temperatures than current superconducting magnets. If realized, HTS magnets would enable stronger, more compact, and more efficient particle accelerators, useful for everything from particle physics and medicine to fusion energy.

"This technology is still very young, and we're helping develop it," Prestemon said. "We had a high-temperature superconducting dipole reach 6 tesla, and that's a record in the field."