They say 'two heads are better than one' and it turns out to be true for electrons as well, as electrons pairing up in certain materials allows them to travel without resistance. These pairings are what lead to superconductivity, but with so many different kinds of high temperature superconductors that behave so differently, the question is what mechanics are common to them all? Researchers at Brookhaven National Laboratory and the University of California, Berkeley believe they are on their way to identifying and explaining that commonality.
Ferromagnetism occurs when the spins of electrons within a material all align and add together to create a large magnetic field. Antiferromagnetism however has some of the electrons aligned in the opposite direction, subtracting from the sum. Some researchers have proposed that it is antiferromagnetic interactions that lead to superconductivity, but this has been difficult to prove because of the number of complicating, intertwined electronic phases that may emerge in a high temperature superconductor. Now these researchers appear to have found a model that describes how these intertwined phases and superconductivity arise from the antiferromagnetic interactions, by considering how antiferromagnetism interacts with the arrangements free electrons can move in, on a conductor.
If accurate, this theory could lead to a much better understanding of high temperature superconductors, and potentially the ability to design such materials. For now though, the theory has to be tested by applying it to newly discovered materials.
Source: Brookhaven National Laboratory