Contact: Paul Preuss
DOE/Lawrence Berkeley National Laboratory
Caption: The interior bulk of a topological insulator is indeed an insulator, but electrons (spheres) move swiftly on the surface as if through a metal. They are spin-polarized, however, with their momenta (directional ribbons) and spins (arrows) locked together. Berkeley Lab researchers have discovered that the spin polarization of photoelectrons (arrowed sphere at upper right) emitted when the material is struck with high-energy photons (blue-green waves from left) is completely determined by the polarization of this incident light.
Credit: (Image Chris Jozwiak, Zina Deretsky, and Lawrence Berkeley National Laboratory Creative Services Office)
Usage Restrictions: with credit as given
Related news release: Surprising control over photoelectrons from a topological insulator