Quantum communication is more secure
than fibre-optic cable, because any
tapping can easily be detected.
• Dr Stef Roux
Principal researcher and project leader
CSIR National Laser Centre
+27 12 841 2823
For some, talk of lasers and quantum physics immediately conjures images from our favourite science fiction movies. But one South African is turning what many people still perceive as fantasy into a reality.
Dr Stef Roux, a researcher and project leader at the Council for Scientific and Industrial Research’s National Laser Centre, is looking to pioneer free space quantum communication, a technology that transmits optical signals through the air using the quantum properties of laser light.
According to Roux, this technology will provide a much safer means of communicating. He added that the point is to communicate by line of sight, from one tower to another, using light.
Roux stated that quantum communication is safer than fibre-optic cables because the latter can be tapped and tampered with, whereas with quantum communication such behaviour can be easily detected.
“In terms of application it will help secure communication. And with online ID theft and fraud, there’s a big challenge to find more secure communication.”
The 47-year-old believes South Africa should act quickly in taking the initiative to develop this technology so that the country can become a global communications role player. He said that in a number of countries, funding and research into this technology is a high priority.
“If we in South Africa jump on this bandwagon and make a significant contribution, it will have a huge impact for the country and position us as a key role player for this technology in the world,” said Roux.
Quantum communications still in its infancy
Roux, who holds doctorates in both electronic engineering and theoretical particle physics, has a passion for optics and particle physics, which is pushing him to advance in the project.
A year in, Roux and his team have progressed far enough to have drawn up theoretical results. However, the practical aspect of the project is still in its infancy and there are challenges in getting the technology to work.
Roux said that the team is still in the process of attaining a proper laser and to achieve stable entanglement. This is a concept of quantum mechanics that describes the action of a pair or group of particles when they behave like one object but remain as individuals.
Quantum entanglement involves photons, or elementary particles, of light which, in the lab, are set up so that when one is manipulated, the others will be affected no matter how far apart they are.
This relates to how senders and receivers will realise that someone is trying to eavesdrop on their communication.
Roux has discovered that the entangled particles are very precarious and that entanglement cannot be retained, especially when the atmosphere is turbulent as this causes the particles to de-cohere. He and his team are currently researching how to mitigate these effects.
Collaborating with universities
Roux hopes to advance the experimental stage soon through collaboration with three universities. He is currently working on the project with the University of KwaZulu-Natal, but will visit Canada’s University of Ottawa in the third quarter of the year to learn more about their findings.
He is also looking to collaborate with the University of Freiburg in Germany.
Roux said the experts at these universities have already established basic experiments to implement the technology and that he can gain valuable experience that would help him with his own experiments.
But if you are expecting to be using this technology soon, look for alternatives in the meantime. According to Roux, no definite date can be set for its availability to the public, as it may take up to a decade to finally turn it into a workable technology.
He also stated that for the technology to grow, it will need protocols and infrastructure.