Description

Modern technology is based on materials called semiconductors. Electronic devices such as computer processors use the elemental semiconductor silcon (Si), while photonic devices such as LEDs and lasers use compound semiconductors such as gallium arsenide (GaAs). The problem is that it is very difficult to combine the two, so photonics and electronics can't easily be integrated.

In the 1990 it was discovered that tiny Si nanocrystals were much better light sources than bulk Si, opening up the possibility of making electronic and photonic devices from the same material. However, there was no agreement on the physical origin of the light from nanocrystalline Si.

In 2008 we published a paper in Nature Nanotechnology which demonstrated that we could distinguish between the two main rival explantions (it turned out that both were right!), and reversibly modify the structure to switch between the two.