Published in Nature Communications: A team of researchers from Australia and China has generated single photons as carriers of quantum information in security systems.
Led by the Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS) at the University of Sydney, the work could ultimately drive forward cybersecurity, along with advancing quantum computing.
Among a number of quantum systems, optical systems offer particularly easy access to quantum effects. However, implementing optical quantum technologies has been held back by the challenge to produce indistinguishable single photons on-demand.
The team’s work provides a path towards resolving this key issue. They show that the odds of being able to generate a single photon can be doubled by using a relatively simple technique - and this technique can be scaled up to ultimately generate single photons with 100% probability.
This also opens up an avenue towards the development of a password exchange that can only be broken by violating the laws of physics. By generating pairs of photons, detecting one indicates the existence of the other. This allows scientists to manage the timing of photon events so that they always arrive at the time they are expected.According to CUDOS director and co-author of the paper Professor Benjamin Eggleton, the interdisciplinary research is set to revolutionise our ability to exchange data securely – along with advancing quantum computing, which can search large databases exponentially faster.
"The ability to generate single photons, which form the backbone of technology used in laptops and the internet, will drive the development of local secure communications systems – for safeguarding defence and intelligence networks, the financial security of corporations and governments and bolstering personal electronic privacy, like shopping online," he said in a university media statement.
"Our demonstration leverages the CUDOS Photonic chip that we have been developing over the last decade, which means this new technology is also compact and can be manufactured with existing infrastructure."
The research will be continued through the Australian Institute for Nanoscale Science and Technology, which launches at the University of Sydney in April 2016.
Researchers from three other Australian unversities - Macquarie University, the Australian National University and the University of Melbourne - and the Guangdong University of Technology, China, collaborated in the study.