Australian researchers unlock the key to cheaper high-tech telecom and medical diagnostic devices.
Scientists and engineers will soon have a much cheaper way of stabilising, blocking and steering light – potentially lowering the costs of high-tech equipment used in telecommunications, medical diagnostics and consumer electronics.
Researchers led by Dr Girish Lakhwani, a chief investigator for the Australian Research Council’s Centre of Excellence in Exciton Science (ACEx), have found a way to manipulate light produced by lasers at a fraction of the cost of existing methods.
For a wide range of modern electronics, including broadband communications and fibre-optic sensors, manipulating light is a critical function. Without the ability to bend and deflect reflected light, for instance, the lasers and amplifiers that are central to broadband networks would be overwhelmed and fail.
The device used to manage light in high-tech systems is called a Faraday rotator. It comprises ferromagnetic crystals surrounded by powerful magnets – which together give operators the ability to adjust the “polarisation”, or alignment of waves, in a light beam.
Faraday rotators are very efficient, but they are also very expensive, requiring terbium-based garnets.
All that now looks set to change. Dr Lakhwani and colleagues have developed a new type of rotator in which the costly garnets are replaced by much cheaper crystals called lead-halide perovskites – a critical component of new generation solar cells.
The crystals have excellent optical properties and low production costs, making them strong candidates for a host of opto-electronic applications beyond renewable energy tech.
“We’ve been looking into Faraday rotation for quite some time,” Dr Lakhwani says. “It’s very difficult to find solution-processed materials that rotate light polarisation effectively. Based on their structure, we were hoping that perovskites would be good, but they really surpassed our expectations.”
Dr Lakhwani is based at the University of Sydney’s School of Chemistry and is a member of SydneyNano Institute. He worked with collaborators from UNSW, as well as ACEx investigators at University of Sydney and Monash University.
The research is published in the journal Advanced Science and can be found here.
A more detailed media release can be found here.