Physicists Find New Type of Magnetism

Physicists have found experimental evidence of a new type of magnetism, called altermagnetism, in a material called Co₁/₄TaSe₂. This type of magnetism has no net magnetization, like antiferromagnets, but its electrons behave as if the material were magnetic.

The researchers, led by University of Central Florida Professor Madhab Neupane, used a technique called angle-resolved photoemission spectroscopy to map how electrons move inside the crystal. They found a characteristic splitting in the electronic bands of Co₁/₄TaSe₂, which is key evidence of altermagnetism.

Altermagnets combine the advantages of ferromagnets and antiferromagnets. They can avoid producing unwanted stray magnetic fields, like antiferromagnets, but also generate and detect spin currents, like ferromagnets.

The material Co₁/₄TaSe₂ is a layered material made of cobalt, tantalum, and selenium. The researchers found that the electronic state associated with altermagnetism originates mainly in the interior of the material, rather than only at the surface.

The discovery of altermagnetism could lead to the development of faster, more efficient computers. Altermagnets could be used to build spintronics, which use electron spin rather than just charge to process information.

LSU Professor Constantin Schrade's research also supports new theories on how altermagnets could be useful to control spintronics. His findings were published in a popular academic journal.

The researchers view Co₁/₄TaSe₂ as a flexible platform for further study of altermagnetism. The material's properties can be changed, and the response of its electronic and magnetic structure can be tracked.