Researchers at the PSI, the EPFL and the Chinese Academy of Science, have proven that the material SmB6 shows all the properties of a so called topological insulator à a material with electric currents flowing along its surface with all of them being polarized. Here, the property is very robust, i.e. the only current that can flow is spin polarized and is not easily destroyed by small irregularities in the structure or composition of the material. Spin polarized currents are necessary for spintronics, electronics using the electrons’ spin.