Photonic Chip-Based QKD Achieves Higher Transmission Speeds
In a research project led by the University of Geneva, ID Quantique (IDQ) has contributed to the development of a quantum key distribution (QKD) system based on integrated silicon photonics that can transmit secure keys at unprecedented speeds. The goal of this project is to show how the use of integrated photonics will provide compactness, low cost, and ease of integration as well as inroads to mass production.
QKD has already established itself as a trusted method of providing forward secrecy for key exchange over distance. Unlike classical key exchange security, which relies on mathematics, QKD relies on the laws of physics. Specifically, it leverages the core principles of quantum mechanics to generate a genuine source of entropy for key generation with the principle that observation causes perturbation to guarantee the integrity and confidentiality of the subsequent key exchange.
In recent years, QKD deployments are flourishing all over the world, notably in Europe through public initiatives, and in China, which started building its own nationwide QKD network about a decade ago by identifying the technology as one priority in their national strategy. Since 2007 when it launched its first commercial QKD systems, ID Quantique has deployed QKD networks and testbeds on all continents. One of these is in South Korea, which is one of the most sophisticated QKD networks, achieving unmatched scalability, usability, and interoperability.
Next generation QKD
This research project is the result of a collaboration between researchers at the University of Geneva and two commercial partners: ID Quantique and Sicoya, a silicon photonics manufacturer headquartered in Berlin. The project team developed a solution that comprised a distributed feedback laser, photonic integrated circuits, and a dispersion-compensating fiber for transmission. The random numbers were seeded by IDQ’s Quantis QRNG.
Low-loss, high-speed transmission, in a chip-based system
The experiment produced key generation and quantum-bit error rates comparable to those of discrete components and fiber-based systems, demonstrating the feasibility of use within integrated QKD solutions. The transmitter proved to be a practical, low-cost option and the low-loss receiver (manufactured by the Institute of Photonics and Nanotechnology in Milano, Italy) was polarization-independent.
In this research project, demonstrations rely on the use of superconducting nanowire, single-photon detectors (SNSPDs) and InGas SPADS, a range of products already mature and commercialized by IDQ.
The next step is to analyze the feasibility of integrating all components on a chip for mass production.
IDQ is constantly working at the forefront of technology to enhance the value for its end users and further deploy QKD technology on large scale networks at a lower price. In 2021, IDQ launched its 4th generation of QKD systems, the XG series. This is a more compact and robust solution that fits requirements to easily deploy QKD both on backbone and metro networks.
In February 2023, a team from UNIGE and ID Quantique reported single-photon detectors with unprecedented performance, increasing their speed by a factor of twenty. This innovation, reported in the journal Nature Photonics, makes it possible to achieve unprecedented performances in QKD distribution, offering new perspectives for ultra-secure data transfer.
Quantum communications are a game changer for today’s cybersecurity already. As quantum computing technology advances and the risk of seeing stored data stolen and decrypted is higher every day, businesses failing to adopt quantum security will likely see their data confidentiality significantly compromised.
For more details, read the published paper entitled, “Chip-based quantum key distribution achieves higher transmission speeds.“
To request more information or a quotation for any ID Quantique products, contact IL Photonics.