Laser electron spin photo

This diagram illustrates how lasers can be used to control an electric current on these new materials.

Electrons (blue spheres) travel, as if on a highway, in different directions, with their axis of spin (arrows) aligned differently according to the direction of travel. A circularly polarized laser beam (left) affects only electrons going in one direction, removing them from the flow, leaving a net flow — an electric current — going the other way.

Photo: Gedik Group