Splitting light in the cloud
NCI’s supercomputer-grade NeCTAR cloud node is helping researchers design more efficient solar cells.
PhD candidate Bjӧrn Sturmberg from the University of Sydney has set up a custom environment on the cloud to research a new type of nanostructure for use in ‘tandem’ solar cells.
The aim is to use these nanostructures to divert different wavelengths of light towards different types of converters within the cell.
“Silicon solar cells are very good at converting short, visible wavelengths into electricity, but they’re not so good at absorbing the longer wavelengths,” he says.
“The idea is that you could add a second solar cell made of a different material that absorbs and converts those longer wavelengths more efficiently.”
Mr Sturmberg is using the NCI cloud environment to design a nanostructure that uses cleverly placed holes to achieve a clean split of light, efficiently directing different wavelengths to the relevant material.
The process requires substantial computer power, he says.
“Light reacts in really weird and wonderful ways when it interacts with a medium that is structured on the same size scale as it – in ways that you don’t normally see in everyday life.
“This means you have to grind out answers to Maxwell’s equations at the nanoscale, and for that you need large computing power.”
The NCI cloud environment is well-suited to Mr Sturmberg’s research because it allows immediate interaction with software outputs.
“I am now able to run simulations that only take a minute, look at them straight away, change something in the model, and run them again,” he says.
“The other great thing is that our collaborators at ANU and other students here at the University of Sydney who want to use the same simulation package that I have developed can access it directly without having to worry about operating systems.”
Backed by the ARC Centre of Excellence for Ultrahigh bandwidth Devices for Optical Systems, an ARC Discovery Grant, and a PhD scholarship from the Australian Renewable Energy Agency, Mr Sturmberg has been collaborating with Dr Thomas White and Prof Kylie Catchpole at ANU to bring his simulations to life in the lab.
“We use NCI to do the modelling to try and understand what physics is going on in these nanostructures and then ANU tests the structures in the lab,” he explains.