New classes of optical devices being developed
Discoveries in nanotechnology are leading to new classes of optical devices, so-called optoelectronic devices, being developed.
Translating electric signals into optical ones and optical signals into electric ones, these devices can more efficiently transfer energy from one type to the other than ever before. Professor Chennupati Jagadish from The Australian National University Research School of Physics & Engineering is working on developing nanowires that can be used in next-generation lasers and solar cells.
The NCI supercomputer allows the research team to model prospective nanowire designs before going through the process of physically producing them. “Modelling becomes very important in terms of designing the devices and understanding the results that we get,” says Professor Jagadish. “By having a state of the art facility like NCI, it really helps us to be able to take up challenging problems and find solutions for them.
Nanowires are very thin tubes of semiconducting materials, 50 nanometres wide and up to 10 micrometres long. This makes them several thousands of times thinner than a human hair. Electrons bounce back and forth inside the nanowire and produce light. “We’re doing a lot of work on engineering these things to the right shape and size so that we can get the properties we are aiming for,” says Professor Jagadish.
Nanowires are the latest in a long line of optoelectronic devices developed by the research group. Over the years, they have studied a variety of nanomaterials, starting with very thick layers of material. They went on to study very thin sheets of material called quantum wells, and then small quantum dots of semiconductive material. These are both now being used for industrial purposes, producing more efficient lasers and LEDs than previous technologies.
After the nanowires, the next step for the research group is to produce nanowires with a quantum well coating. By wrapping certain nanowires in the sheets of quantum wells, new and unusual properties have been observed. These quantum well tubes are one of the new directions for the researchers, along with investigating connections between neuron growth and nanowires.
The cooperative aspect of the work is what makes for scientific progress says Professor Jagadish, “Together we are doing outstanding work. By choosing the right collaborators that are experts in their own field, collectively we can make a huge difference.”