This is Tim Burgess with a silicon wafer on which nanostructures are grown. Credit: Stuart Hay, ANU
This will help in development of low-cost biomedical sensors, quantum computing, and a faster internet. Researcher Tim Burgess added atoms of zinc to lasers 1/100 the diameter of a human hair and made of gallium arsenide – a material used extensively in smartphones and other electronic devices. The impurities led to a 100X improvement in the amount of light from the lasers.
“Normally you wouldn’t even bother looking for light from nanocrystals of gallium arsenide – we were initially adding zinc simply to improve the electrical conductivity,” said Mr Burgess, a PhD student, ANU. “It was only when I happened to check for light emission that I realised we were onto something.”
Gallium arsenide is a common material used in smartphones, photovoltaic cells, lasers and light-emitting diodes (LEDs), but is challenging to work with at the nanoscale as the material requires a surface coating before it will produce light. Previous ANU studies have shown how to fabricate suitable coatings. The new result complements these successes by increasing the amount of light generated inside the nanostructures.
“It is an exciting discovery and opens up opportunities to study other nanostructures with enhanced light emission efficiency so that we can shrink the size of the lasers further,” he said. Mr Burgess said that the addition of the impurity to gallium arsenide, a process called doping, improved not only the light emission. “The doped gallium arsenide has a very short carrier lifetime of only a few picoseconds, which meant it would be well suited to use in high speed electronics components.
http://www.anu.edu.au/news/all-news/a-little-impurity-makes-nanolasers-shine
Recent Comments