Silicon-based material with a direct band gap is the Physics World 2020 Breakthrough of the Year

Physics World ^ | 17 Dec, 2020 | Hamish Johnston

[MtnClimber]

The Physics World 2020 Breakthrough of the Year goes to Elham Fadaly, Alain Dijkstra and Erik Bakkers at Eindhoven University of Technology in the Netherlands, Jens Renè Suckert at Friedrich-Schiller-Universität Jena in Germany and an international team for creating a silicon-based material with a direct band gap that emits light at wavelengths used for optical telecommunications.

It is no exaggeration to say that finding a silicon-based material that emits useful light has been the Holy Grail of optoelectronics. Normally, silicon has an indirect electronic band gap, which means that it does not emit light. As a result, silicon must be integrated with other direct-band-gap semiconductor materials to create the optoelectronic devices that supply the pulses of light that drive information on the Internet. While this integration is possible, it is difficult and expensive.

To create a direct band gap, Bakkers and colleagues had to find a way of growing crystals of silicon-germanium alloy with a hexagonal crystal structure, rather than the usual diamond-like structure. They did this by creating nanowires of the alloy, which emitted infrared light. As well as having applications in optical telecoms and optical computing, the new silicon-based material could be used to create chemical sensors.

[zeestephen]

Just to be sure...

You know that silicon is an element, and silicone is a man made polymer, right?

[mfish13]

Silicon is not that plentiful. Now SiO2 is very plentiful but requires a lot of energy to breake down to silicon so that silicone, silanes and siloxanes that are used in industry are made.