Spins Swapped At a Distance
Spin is a fundamental aspect of quantum mechanics and from it we get the magnetism that pins things to our refrigerators, as well as other interactions. This makes studying it very important as a means to understand the phenomena around us. Recently researchers at JILA, a joint institute with NIST and the University of Colorado, Boulder observed spin-states being swapped between molecules, even when they were relatively far apart.
Spin swapping is not a new phenomenon to observe, but this is the first time it has been observed with molecules, instead of atoms. To achieve this, the researchers worked with ultracold gas molecules. At such low temperatures, external forces that would act on the potassium-rubidium molecules are minimized or removed. This particular molecule was selected because it is polar, with the rubidium atom possessing a positive charge and the potassium atom a negative charge, and that allowed the researchers to trap them in an optical lattice. The lattice kept the molecules separated, so any interactions between them would be guided by internal properties, instead of chemical reactions.
This experiment will likely affect many areas of research because of how powerful spin states are. Potentially the system the researchers developed could be used to simulate and even invent exotic materials with special properties born from spin behavior. Such materials could include high-temperature superconductors and topological insulators.