Edinburgh to host European quantum light tour

Scotland is to host a quantum light source that is travelling across 12 countries in Europe.

Heriot-Watt University in Edinburgh is the only Scottish stop on the tour – called the QuanTour – which aims to raise interest in quantum physics ahead of next year’s UNESCO International Year of Quantum Science and Technology 2025.

The quantum light source is a device that produces single particles of light, called photons. By engineering on a microscopic level, scientists are harnessing the physics of these single photons to develop ultra-high performance applications, including more powerful computing and unconditionally secure communications.

At Heriot-Watt, the QuanTour will arrive today (Monday 11 November) at the lab of Brian Gerardot, an expert in quantum photonics – the science of light – who is a Professor of Physics at Heriot-Watt’s School of Engineering and Physical Sciences and head of the University’s Institute of Photonics and Quantum Sciences (IPAQS).

IPAQS carries out a wide range of world-leading research in photonic physics, engineering photonics and quantum sciences, building on Heriot-Watt’s 40+ years legacy in global photonics research.

Professor Gerardot said: “We’re very excited to be hosting the QuanTour light source. It’s a great opportunity to connect with the research community in this area and also to celebrate the International Year of Quantum Science and Technology.

“Heriot-Watt has been at the forefront of this field of quantum optics for more than 25 years and a lot of the technology behind the quantum light source has been developed here and in the other laboratories taking part.”

From its starting point in Germany, the QuanTour is visiting labs in Austria (Linz), Italy (Rome), Switzerland (Basel), Spain (Madrid), France (Paris), England (Cambridge), Ireland (Cork), Scotland (Edinburgh), the Netherlands (Leiden), Denmark (Copenhagen), Sweden (Stockholm) and Poland (Wrocław). The quantum light source is being carried in a silver metal case and will arrive in Scotland from Cork in Ireland, before heading to Leiden in the Netherlands.

The tour aims to show how photons are being used in quantum communication and why this is important.

“Using single photons to encrypt data makes communication completely unhackable,” explained Frederik Brooke Barnes, a Postgraduate Research Student working with Professor Gerardot and an expert in quantum cryptography – which broadly involves using quantum mechanics in cybersecurity.

“It means that someone trying to eavesdrop on the information being sent can’t do so without being detected. This means that the information is always going to be secure and is guaranteed by the laws of physics.”

The quantum light source was built at Technische Universität Berlin, a research university in Berlin, and generates photons using a ‘quantum dot.’

This is a tiny structure made of semiconductor materials commonly found in our mobile phones, but in this case shrunken to just a few nanometres in size.

A nanometre is one billionth of a metre. The quantum dot is embedded in a bull’s eye-like structure, which acts like mirrors to direct the single particles of light into a beam that can be transmitted long-distances.

“The bull’s eye is about 20 times smaller than the width of a human hair,” Frederik explained. “And the quantum dot is about 1,000 times smaller than that!”

Frederik and fellow PhD student Sheena Shaji have organised a welcoming event for the QuanTour, including a Scottish bagpiper.

During its three-week stay at Heriot-Watt, the team will measure and record the characteristics of the photons produced and share this data with the other quantum teams taking part.

Although the QuanTour’s visit to Edinburgh won’t be open to the public, Heriot-Watt University is hosting a separate Single Photon Workshop event that is open to all. This takes place at the Edinburgh International Conference Centre over five days from 18 to 22 November, 2024, and will showcase cutting-edge advances in photonics and quantum technology.

The UNESCO International Year of Quantum Science and Technology 2025 is a year-long, worldwide initiative to increase public awareness about the importance of quantum science and its applications.

The year 2025 was chosen for this international year because it recognises 100 years since the initial development of quantum mechanics.

UNESCO – the United Nations Educational, Scientific, and Cultural Organisation – is a United Nations agency that promotes international cooperation in education, sciences and culture.

The United Nations is an international organisation founded in 1945 after the Second World War to find shared solutions to common problems. It currently has 193 Member States.

Professor Brian Gerardot has been researching quantum photonics for around 25 years and holds a Chair in Emerging Technologies from the Royal Academy of Engineering. He has a Bachelor of Science degree in Materials Science from Purdue University in Indiana, United States, and a PhD from University of California, Santa Barbara.

Frederik Brooke Barnes has a Master of Physics degree from the University of Manchester and is researching the science of quantum cryptography with quantum dots for his PhD at Heriot-Watt University.

Sheena Shaji has a Master of Physics degree from the Indian Institute of Science Education and Research in Thiruvananthapuram, India, and for her PhD at Heriot-Watt University is researching a technique to collect light from multiple quantum dots on one chip to study their interactions.