A new type of magnetism has been discovered in graphene

In a study published in Science, a group of Stanford physicists announced that they had discovered a new type of magnetism in graphene, called orbital ferromagnetism. The discovery, according to the same researchers, could prove useful for applications in the field of quantum computing.

The researchers were not looking for what they later discovered. It is David Goldhaber-Gordon himself, a professor of physics at Stanford, who admits the accident of the same discovery. In fact, scientists were trying to reproduce an experiment related to the superconductivity of graphene.

Physicists have in fact theorized that by arranging graphene in a particular way, it is possible to collapse the energy states of electrons in matter, something that causes the speed of the movement of electrons to drop to almost zero. At such a low speed, every single electron becomes highly dependent on those in its vicinity. The interactions between electrons in this state are important in many exotic quantum states of matter.

Trying to reproduce this concept in the laboratory, the researchers did various tests and made some seemingly insignificant changes. However, these changes also led to an effect known as Hall voltage (or Hall effect), an effect that showed that graphene was generating its own internal magnetic field. It is a type of magnetism that does not seem to be the result of the alignment of electrons, as in the case of classical magnetic materials, but which instead seems to derive from coordinated orbital movements.

“This is the first known example of orbital ferromagnetism in a material,” says Goldhaber-Gordon.