WE SHOULD have known there was something in it when Microsoft got involved. Back in 2003, the software giant began sponsoring a small research effort with an interest in an abstruse area of physics known as the fractional quantum Hall effect. The effect, which has been the subject of two Nobel prizes, involves the delicate manipulation of electrons inside semiconductor crystals. What could a software company like Microsoft hope to gain from funding this research?
The answer is now clear. This year, we have seen the first indications that this strange and abstract phenomenon could bring us a revolution in computing. “We have good reason to believe that, if we can do anything [with this], we can do a lot,” says Michael Freedman of Microsoft-sponsored Station Q research group in Santa Barbara, California.
Microsoft is interested because an ability to manipulate the fractional quantum Hall effect promises a unique and powerful way to process information using the resources of the subatomic world. Down at the level of photons, electrons, protons and atoms, matter behaves very differently from what we are used to. These quantum objects can be in two places at once, for example, or spin clockwise and anticlockwise at the same time. This phenomenon, known as superposition, is entirely foreign to the way things work in the ordinary “classical” world.
It was realised years ago that superposition provides an opportunity for information processing, and researchers have been working for decades to build a “quantum computer” that exploits it. Encode a 0 as the clockwise spin of an electron and 1 as the …
