Invited Talk: ''High-speed QKD: Removing the Roadblocks for an Integration and Utilization in Real-World Networks''

Tue, 15 Aug , 11:30 - 12:15

    Abstract: The attention towards Quantum Key Distribution (QKD) as means of secure communication is expanding more than ever. However, in order to widely deploy such systems in real-world telecommunications networks, a few more obstacles have to be surpassed. A couple of these were tackled in our group via the usage of the 3-state BB84 time-bin protocol with 1-decoy state. One challenge involves increasing the rate of secret key production. We will discuss how we managed to achieve one of the highest secret key rates by using a multipixel superconducting nanowire single-photon detector, as well as high-speed electronics and fast post-processing. Another obstacle for real-world deployment of QKD regards the merging of classical and quantum channels (CC and QC, respectively) into one single fiber-optic cable. This is highly motivated due to the high costs of fiber deployment, thus the usage of existing fibers is deeply engaging. The challenge of the implementation resides in the noise that appears due to the strong CC with respect to the single-photon-level QC. We will present a case study that was done in our group using the QC at 1310 nm and the CC at 1550 nm. Finally, we will also present the implementation of the used protocol into a more practical setup with integrated photonics. Effectively, the non-practicality of fiber-based, complex QKD setups is another issue. By integrating the QKD setup, we can simplify the implementation and allow for low-cost mass-production.

    Bio: After having completed her masters degree in the department of Nuclear and Corpuscular Physics at the University of Geneva in 2019, Rebecka joined the group of Hugo Zbinden at the same university in the department of Applied Physics. The main focus of her work is within the field of Quantum Key Distribution (QKD), where she have collaborated on projects involving the combination of classical and quantum channels in the same fiber optic cable (through wavelength division multiplexing) and the improvement in the rate of secret key production. Her group now works mainly on the implementation of a QKD system using photonic integrated circuits (PICs). Recently, their employment for usage with QRNGs has also become a primary interest.