Securing online communications with the practical implementation of continuous variable quantum key distribution
Jo茫o dos Reis Fraz茫o defended his PhD thesis at the Department of Electrical Engineering on September 23rd.
The rise of quantum computers promises breakthroughs in science and technology, but it also poses a serious threat to digital security. That鈥檚 because currently, cryptographic systems are used to protect everything from online banking and healthcare records to governmental communications. These systems rely on mathematical problems that are extremely difficult for classical computers to solve, but future quantum computers will be able to crack them quickly. One of the solutions to protect our sensitive data in the future is quantum key distribution (QKD), which uses the laws of physics rather than mathematics to secure communication. Within his PhD research, Jo茫o dos Reis Fraz茫o focuses on a practical implementation of continuous-variable quantum key distribution (CV-QKD).
Unlike conventional cryptography, QKD is provably secure against any attacker, even a quantum computer. developed and tested CV-QKD systems within his research, using both fiber-optic cables and free-space optical links. This approach is especially attractive because it works with existing telecom infrastructure, making it more cost-effective and scalable than alternatives.
Developing a receiver and transceiver
A key achievement in this research was developing a real-time receiver powered by graphical processing units, enabling advanced digital signal processing and efficient handling of quantum signals. The research also shows that quantum and classical data can travel together on the same channels without reducing security, an essential requirement for future integration with existing classical networks. Finally, a compact CV-QKD transceiver device based on photonic integration was demonstrated. This is a step towards energy-efficient and scalable quantum communication systems.
Quantum-safe internet for the future
This research indicates a pathway towards practical and secure communications exploiting CV-QKD technology for the coming quantum era. This technology could form the backbone of a quantum-safe internet, ensuring that our digital world remains protected even in the face of powerful future computers.
Title of PhD thesis: . Supervisors: Prof. Chigo Okonkwo and Dr. Boris Skoric.