The wings of the Green Hairstreak butterfly – Callophrys rubi – have inspired Australian-led research that could increase the speed at which data can be transmitted and received through optical networks.
The Green Hairstreak's wings comprise interconnected nanoscale springs that are sensitive to circularly polarised light. These structures give the butterfly's wings their bright green colour. University researchers have built a photonic crystal inspired by the structure of the butterfly's wings that possesses properties not found in naturally occurring crystals.
Although transmissions through optical fibre travel at the speed of light, the process of sending, receiving and processing this information at either end is significantly slower.
However, the new crystal, which can be used with circularly polarised light, may lay the basis for chips that rely on photons instead of electrons – Min Gu, director of the Centre for Micro-Photonics at Swinburne University, says spiral light structures can transmit more information and increase bandwidth.
Terabit speeds have already been transmitted. For example, a recent 1Tbps trial between Sydney and Melbourne by Telstra.
However, Ben Cumming, postdoctoral research fellow at Swinburne University of Technology and one of the authors of the research, says that the problem generally remains efficiently processing the information at the destination, and that the new kind of beam splitter could play a role in developing systems to speed this up.
“When information is transmitted at large bandwidths such as the 1 Tbps speeds trialled by Telstra, a problem soon arises – how do we process all that information?,” Cumming said.
“Currently, optical techniques such as wavelength demultiplexing are used to split the incoming data into multiple slower electronic systems that are running in parallel (similar to the use of multiple cores in PCs),” he says.
“We want to see the individual processing systems operate much faster, potentially at 1000 Tbps, so that fewer are needed in parallel to process the high bandwidth signals.”
The research collaboration includes 15 academics from Swinburne University of Technology in Australia and Friedrich-Alexander Universität Erlangen-Nürnberg in Germany.
Gu has been working on the project for 10 years and expects it will be another five to 10 years until the technology is employed commercially.
The project is being funded by the Australian Research Council, with a total of $12 million scheduled to be provided to the project for the next four years. Additional funding has also come from seven constituent universities and 15 partner organisations.
“In reality we need much more money – probably two or three times more than this to achieve the final goal,” Gu says.
The researchers are now looking to industry to provide extra funding, with a showcase to industry to be held in Sydney in November and the academics heading to Silicon Valley to commercialise the technology for real world applications.