The EuAuBi crystal is like a layered cake of europium, gold, and bismuth atoms. When cooled to near absolute zero, three different magnetic patterns appear in sequence, like a kaleidoscope pattern shifting with a slight turn. First, the magnetic atoms align strictly in antiphase, then they tilt slightly, and at even lower temperatures, a third order emerges.
In a magnetic field from 1.5 to 3 tesla (tens of thousands of times stronger than Earth's field), real vortices of magnetic moments twist within the crystal. The electrical resistance behaves unusually — electrons flying through these vortices seem to dodge invisible obstacles.
Such a combination of magnetic vortices and massless electrons is extremely rare. It opens the door to new ways of controlling electric current — for example, switching it without heat, using only a magnetic field.
The magnetic transition temperatures in EuAuBi are 4, 3.5, and 2.8 kelvin. That's colder than outer space, which is about 2.7 kelvin.
In science fiction, massless electrons in graphene and other materials are often described as 'liquid light'—here, that image gains a real foundation.