New Fermi Arcs Discovered Could Be The Future of Electronics
Researchers have discovered new magnetism control capable Fermi arcs, believed to be the future of spin electronics. A team from Ames Laboratory and Iowa State University, alongside collaborators from the United Kingdom, United States, and Germany, made the discovery.
The team came by the discovery while investigating the unique neodymium-bismuth. The examination led the group to find a novel kind of Fermi arc that emerged when the material lost its ferromagnetism characteristics at a certain temperature.
In metals, a Fermi surface is a mutual space that diverges electron states at zero temperature. Fermi surfaces usually come in closed contours that form shapes like spheres. Fermi surface electrons control different material properties, like conductivity, etc.
Adam Kaminski, the lead researcher, indicated that the new Fermi arcs are products of electron band dispersion. In turn, this process is caused by the ordered magnetism in particles that form about half of the sampling. But the electron splitting they detected in NdBi didn’t exhibit the typical band splitting behavior.
Zeeman and Rashba are the two main types of band splitting. In both types, the bands maintain their original shape after splitting. However, the new Fermi arcs had two bands ending in different shapes. As the temperature dropped, the space between the bands also increased, but the shapes changed, which implies a change in fermion mass.
According to Kaminski, the process of splitting he observed is not common at all. Part of its uniqueness is because the space between bands increased, and the shape changed, which is unusual. He added that the team observed something that is unlike anything else.
Kaminski also suggested that the Fermi arc his team discovered appears when the model becomes antiferromagnetic. The arc goes away when the magnetic order is back. He stressed how important the discovery is but added that a lot needs to be done before introducing it to new technology.