Two materials that have been recently discovered and could drastically affect the future of technology are graphene and topological insulators. Both have intriguing electrical properties stemming from their 2D Dirac fermions. Researchers using Berkeley Lab's Advanced Light Source (ALS) have recently discovered a three-dimensional topological Dirac semi-metal (3DTDS), which is a three dimensional counterpart to those other two materials.
Graphene is an atom-thick sheet of carbon and topological insulators have the unique property of conducting electrons on their surface, but not through their bulk. Both have extraordinarily high electron mobility as a result of their two-dimensional topologies, which led researchers to wonder if this and other properties could be reproduced in the bulk of a material, with three-dimensional topology. The researchers have found that sodium bismuthate is such a material, and it comes with more than just high electron mobility. It also features, as a result of being a 3DTDS, non-saturating linear magnetoresistance many times greater than other materials. What that translates to is that it could be used to increase the storage capacity of a hard drive significantly.
One catch to this research though is that sodium bismuthate is not something that could be easily applied to many technologies. This work has not been a waste though because it can allow researchers to study the behavior of a 3DTDS while searching for one better suited for use.
Source: Berkeley Lab