A research team at the University of Sydney, along with fellow collaborators, have made a breakthrough

According to the researchers, today, with enough computing power, most security systems can be broken. This may not be the reality for long, however, as the team has figured out how to generate single photons (light particles), as carriers of quantum information in security systems, and says this could be a game changer.

The collaboration involving physicists at the Centre for Ultrahigh bandwidth Devices for Optical Systems (CUDOS), an ARC Centre of Excellence headquartered in the School of Physics, and electrical engineers from the School of Electrical and Information Engineering, has been published today in Nature Communications.

The team's work resolved a key issue holding back the development of password exchange, which can only be broken by violating the laws of physics, using quantum technologies.

Lead author, Dr Chunle Xiong, from the School of Physics, says, "Quantum communication and computing are the next generation technologies poised to change the world. Among a number of quantum systems, optical systems offer particularly easy access to quantum effects. Over the past few decades, many building blocks for optical quantum information processing have developed quickly.

"Implementing optical quantum technologies has now come down to one fundamental challenge: having indistinguishable single photons on-demand. This research has demonstrated 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,” he says.

Professor Ben Eggleton, CUDOS director and co-author of the paper, says the interdisciplinary research was 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," Eggleton says.

"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,” he says.

Co-author and professor of Computer Systems, Philip Leong, who developed the high-speed electronics crucial for the advance, says he was particularly excited by the prospect of further exploring the marriage of photonics and electronics to develop new architectures for quantum problems.

"This advance addresses the fundamental problem of single photon generation - promises to revolutionise research in the area," Leong says.

The group - which is now exploring advanced designs and expects real-world applications within three to five years - has involved research with University of Melbourne, CUDOS nodes at Macquarie University and Australian National University and an international collaboration with Guangdong University of Technology, China.