Settling the debate: Solving the electronic surface states of samarium hexaboride
(PHYSorg.com Physics)

A team led by Osaka University used angle-resolved photoelectron spectroscopy to probe the unusual surface conductivity of samarium hexaboride crystals. They showed that the material is a co-existing phase of `topological insulator` in which electrical current can flow along the surface but not through the bulk of the sample, a `Kondo insulator,` which undergoes a metal-to-insulator transition due to the strong electron correlation. This work, which demonstrates that topological insulators can simultaneously have strong electron correlations, may allow for the development of quantum spin devices that use the magnetic spins of individual electrons to outperform current computers.