A closer look
Normally, a material is either a conductor like copper or an insulator like rubber. Topological insulators like bismuth antimony violently reject this binary. Deep inside the bulk of the crystal, electrons are trapped, making it impossible for current to flow. However, on the extreme outer atomic edges, electrons race around at nearly the speed of light. Even crazier, due to 'spin-momentum locking,' the electrons on the surface physically cannot be scattered or slowed down by defects or impurities in the metal. The underlying mathematics of their quantum state guarantees this perfect surface conduction, paving the way for insanely fast, zero-heat quantum computers.
