Who is Prof. André Xuereb?
Six questions to a quantum physicist securing our communications.
What do you do?
“I am a quantum physicist from Malta, and since October 2019 the Head of the Physics Department at the University of Malta. I work a lot on optomechanics, which is the study of how light interacts with moving objects, with the aim to create technologies, i.e., new communications systems, sensors and computers that use light instead of electricity. Recently I started focusing on quantum-secured communications, which solves the issue of how to communicate securely, with an absolute certainty that no one is intercepting that communication.
One of my research highlights was to implement safe quantum communications technologies in real-world environments. Through an international project involving research teams from Malta, Italy and Austria, we established a quantum communication channel between Italy and Malta over existing underwater optical fibres in the summer of 2017. In the long run, this project will help protect Maltese critical infrastructures and will pave the way for quantum communications to be used between Malta and Italy but also elsewhere.”
What is your biggest challenge?
“In quantum physics it is easy to get lost in the detail and go down the rabbit hole. Balancing the love I have for asking science’s fundamental questions with the realisation that quantum mechanics is increasingly becoming a commodity with which to create new technologies is an interesting challenge.”
What are your most recent achievements?
“Three major recent results of my collaborators and myself are based on the underwater secure communications experiment we made between Malta and Italy.
In the first experiment, particles of light travelled inside an undersea cable connecting the two countries’ telecommunications networks. We demonstrated the possibility of sharing a quantum property, called entanglement, between countries over this distance. Our work set two records for the longest distance over which this has been done: 96 km and 192 km. This work can be exploited to develop international communications networks that cannot be hacked.
During the same period, the team demonstrated that submarine optical fibres are stable enough to send and receive ultra-precise time signals over very large distances. This technique makes it possible to synchronise the most precise clocks known to man, even if these are far away from each other. This can, for instance, assist banks in speeding up transactions and scientists in increasing the precision of their results by conducting simultaneous experiments in laboratories all over Europe.
Finally, we demonstrated how ultra-stable lasers can be used to turn the global telecommunications network into a sensitive microphone for tiny earthquakes in remote regions of the globe. These results could have significant implications for the study of our planet and for earthquake early-warning systems.
The achievements of this seminal work led directly to NATO’s Science for Peace and Security (SPS) Programme’s Multi-Year Project ‘Secure Quantum Communication Undersea Link’ or ‘SEQUEL’, which I am currently working on in collaboration with the Istituto Nazionale di Ottica (INO, Italy) and the Istituto Nazionale di Ricerca Metrologica (INRiM, Italy).”
What is the value of the NATO SPS Programme in this area?
“The NATO SPS Programme is unique in my experience. It allows a small consortium to push forward specific technologies at a scale that does not easily fit in any other programme supporting scientific cooperation. It also has a broad remit, encompassing cyber security, quantum technologies, sensing and many other areas.”
What is your favourite part of your job?
“Talking about science! I make it a point to visit schools, speak to politicians and give interviews – anything that helps me transmit the message of how important science is to society and how essential it is for science to be funded. Interestingly, schoolchildren often ask the best questions. Perhaps adults should work better to maintain a childlike curiosity in the world around them.”
What don’t your colleagues know about you?
“Despite not having much musical talent, I played guitar in a rock band for several years when I was in high school and at university. I still keep one of my guitars in my office so that students think I am cool.”
Professor Xuereb is a project director from NATO partner country Malta in the Multi-Year Project "Secure Quantum Communication Undersea Link” in the framework of the NATO Science for Peace and Security (SPS) Programme. This SPS activity brings together scientists from Italy and Malta to establish an undersea quantum key distribution link between the two countries – the first ever on this scale. This link is a key step in setting up a stable and secure communications system.
"Scientists of NATO" introduces some of the experts involved with the SPS Programme. The Programme promotes dialogue and practical cooperation between NATO member and partner nations based on scientific research, technological innovation and knowledge exchange. It offers funding, expert advice and support to tailor-made, security-relevant activities that respond to NATO's strategic objectives.