Topological insulators: next gold rush ?

At this year’s APS meeting, however, the hallways were filled with talk of a promising newcomer— an eccentric class of materials known as topological insulators. The most striking characteristic of these insulators is that they conduct electricity only on their surfaces. The reasons are mathematically subtle — so much so that one physicist, Zahid Hasan of Princeton University in New Jersey, tried to explain the behaviour using ‘simpler’ concepts such as superstring theory. (“It’s awfully beautiful stuff,”
he said reassuringly.) Yet the implications are rich, ranging from practical technology for quantum computing to laboratory tests of advanced particle physics.