17 January 2014
Nature: Sheets of graphene are only one-carbon-atom thick, and the arrangement of the atoms produces unusual electrical properties. The electron energy levels form cones that allow electrons to flow relativistically through the material. Now, three groups of researchers have found two different three-dimensional crystals that reproduce this behavior. One group examined trisodium bismuthide, and the other two examined cadmium arsenide. All three groups bombarded the crystals with photons to study the structure of the electron energy levels both on the surface and inside the crystals. The similarity of the crystals' electronic structure to that of graphene, paired with a stronger connection between the crystals' electric and magnetic properties, may make them useful in high-density storage systems and in the development of spintronics, in which data are encoded using particle spin.