The prediction and subsequent discovery of robust spin-polarized surface states on topological band insulators has launched a new subfield of physics over the last decade.
25 April 2016
Topological insulators are a novel class of materials that exhibit a novel state of matter - while the inside (bulk) of the materials are electrical insulating, their surface is metallic. This effect occurs because the band structure of the materials is topologically different (in a mathematical sense) from the outside world.