Physicists at the University at Buffalo have proposed a quantum sensing technique that could identify altermagnets using tiny defects in diamond. The method would help confirm the properties of these recently theorized materials. It was detailed in a paper published in Physical Review Letters.
The approach relies on a nitrogen-vacancy defect in diamond that is highly sensitive to magnetic fields. Researchers would rotate the defect's spin and monitor its relaxation rate to spot the distinctive spin patterns expected in altermagnets.
Altermagnets were first proposed in 2019 by scientists including Libor Šmejkal and Jairo Sinova. These materials show no net magnetization yet exhibit electronic behaviors similar to ferromagnets, potentially enabling faster and more efficient data processing than current technologies.
Corresponding author Jamir Marino said the technique "could be the first building block of a new generation of experiments that determine whether a material is an altermagnet." Co-author Sinova noted it offers advantages by detecting subtle patterns without strongly disturbing the sample.
The proposal remains theoretical and requires experimental validation. The work was supported by the German Research Foundation and includes additional co-authors from institutions in Germany and France.
