A collaboration of researchers at the U.S Department of Energy’s Lawrence Berkeley National Laboratory has discovered that sodium bismuthate can exist as a form of quantum matter called a three-dimensional topological Dirac semi-metal. This is the first experimental confirmation of 3D Dirac fermions in the interior or bulk of a material, a novel state that was only recently proposed by theorists.
As two-dimensional graphene has become one of the most lusted-after materials in science, many have wondered if there might be a 3D counterpart that we could actually build things with. A team of scientists at the Berkeley Lab just offered an affirmative answer. Well, almost. A team lead by Oxford’s Yulin Chen just confirmed that a sodium-bismuth compound, Na3Bi, holds many of the same properties of graphene with the luxury of being thicker. This three-dimensional quantum matter was tested at Berkeley Lab’s Advanced Light Source and was shown to conduct electricity as well if not better than graphene. On top of that, the scientists also believe that it will work as a topological insulator, a material that’s conductive on the surface but insulates in bulk.
