A one-way street for spinning atoms
Elementary particles have a property called “spin” that can be thought of as rotation around their axes. In work reported this week in the journal Physical Review Letters, MIT physicists have imposed a stringent set of traffic rules on atomic particles in a gas: Those spinning clockwise can move in only one direction, while those spinning counterclockwise can move only in the other direction.Physical materials with this distinctive property could be used in “spintronic” circuit devices that rely on spin rather than electrical current for transferring information. The correlation between spin and direction of motion is crucial to creating a so-called topological superfluid, a key ingredient of some quantum-computing proposals.The MIT team, led by Martin Zwierlein, an associate professor of physics and a principal investigator in the Research Laboratory of Electronics (RLE), produced this spin-velocity correlation in an ultracold, dilute gas of atoms. Just like electrons, the atoms in the...