Research Areas

Quantum Communications

Quantum Communications is a research field that harnesses the fundamental laws of quantum mechanics to transmit quantum states of light. Unlike classical communication systems, where the information carrier consists of classical bits represented as "0" and "1", quantum communication systems store and transmit information using "qubits." A qubit is a quantum bit that, unlike classical bits, can exist in multiple quantum states simultaneously, a phenomenon known as superposition. This unique property enables information processing in a much more secure and efficient manner. Quantum Key Distribution (QKD) is an instance of quantum communication between remote parties that deals with the distribution of qubits over an optical fiber or free space channels. The information stored in the qubits is used to securely transfer symmetrical encryption keys. QKD relies on the no cloning theorem of quantum mechanics to ensure the security of the key distribution process. Thus, any attempt to eavesdrop on the transmission (measurement of the quantum state) will inevitably introduce detectable changes in the quantum states, allowing the users to detect eavesdropping. Consequently, the implementation of QKD in real-world scenarios has the potential to offer a substantial degree of security for confidential information. This renders QKD an important area of study for the secure distribution of critical data in fields such as governmental and healthcare facilities, financial industry, and more.

PCRL research activities on Quantum Communications involves the experimental investigation and design of photonic platforms for quantum communication systems, with a focus on the integration of QKD in practical deployments as well on the use of photonic integration concepts in support of efficient QKD stations. Research topics within QKD target both FSO, satellite and fiber-based implementations both for Entanglement-based and Prepare and Measure-based protocols. PCRL has participated in various European research projects focusing on quantum communication technologies, namely UNIQORN, Hellas-QCI, QSNP and LaiQa, aiming at advancing quantum communication technology and incorporate QKD systems into existing communication infrastructures to provide an extra layer of security.