For nearly a century, there were two known kinds of magnets. Ferromagnets are the classic magnets that attract metal and keep pictures stuck to the refrigerator. Antiferromagnets hide their magnetism at the atomic scale but are increasingly prized for their technological potential. A third category discovered within the last decade may combine the best qualities of both. Dubbed altermagnets, they could someday help create faster, more energy-efficient electronics.
Now, University at Buffalo physicists are proposing a quantum sensing system to make identifying altermagnets much simpler. Described in a study published in Physical Review Letters, the theoretical technique would measure how a suspected altermagnet disturbs a tiny magnetic defect in a nearby diamond. The way the defect’s magnetic signal relaxes could provide evidence of altermagnetism.
“This could be the first building block of a new generation of experiments that determine whether a material is an altermagnet,” says corresponding author Jamir Marino, Ph.D., assistant professor in the UB Department of Physics, College of Arts and Sciences. “Altermagnets could completely revolutionize the way we transport information, but to confirm if this elegant theory is true, we need experiments that identify altermagnets and confirm they behave the way scientists predict.”
