There are several slogans and clichés that prevent the idea of the outside of something being very different from the inside. For some reason I doubt whoever created those sayings were thinking about topological insulators which are highly conductive on their surface, but insulators within their volume. This unique pairing could be key to creating quantum computers in the future, and researchers at Boston College have just made an interesting discovery that could help bring that future closer to the present.
Before the insulators can be used in any device, we have to find some way to control the electrons traveling on them, which is what the researchers discovered, but did not expect. The researchers changed the topography of the insulator to look like ripples on the surface, and when the electrons flowed over it, they followed that pattern and took on a sinusoidal potential. We already know electrons travel differently on topological insulators than most other materials, as they obey relativity, but this ability to impose a new potential by changing the surface has not been seen before.
This ability to have a physical structure affect the potential of the electrons could lead to some very interesting possibilities, including making a one-dimensional wire that transmits the electrons without resistance. That will definitely be useful in the future for far more than just quantum computers.