Multiple Quantum Key Distribution Research Articles

Low-cost lightweight-client twin-field quantum key distribution network with wavelength division multiplexing

In recent years, quantum communication technology has gradually entered the practical stage. Multiple quantum key distribution (QKD) networks have been built and tested all over the world. However, quantum communication networking mode always evolves from a point-to-point network to a many-to-many network. The major challenges in quantum communication are secret key rate, distance, cost, and size of QKD devices. We proposed a low-cost, lightweight-client, twin-field QKD network with wavelength division multiplexing (WDM). The proposed implementation adopts polarization multiplexing, time-division multiplexing, and WDM technology to solve all these major challenges and implement a many-to-many dynamic communications network. Furthermore, our scheme can effectively reduce the cost to less than half of that of current QKD networks and has reference significance for large-scale deployment of QKD networks.

Modeling optical fiber space division multiplexed quantum key distribution systems.

We report a model to use to evaluate the performance of multiple quantum key distribution (QKD) channel transmission using spatial division multiplexing (SDM) in multicore (MCF) and few-mode fibers (FMF). This model is then used to analyze the feasibility of QKD transmission in 7-core MCFs in two practical scenarios involving the (1) transmission of only QKD channels and (2) simultaneous transmission of QKD and classical channels. In the first case, standard homogeneous MCFs enable transmission distances per core compatible with transmission parameters (distance and net key rate) very close to those of single-core single-mode fibers. For the second case, heterogeneous MCFs must be employed to make this option feasible.

Experimental investigation of high-dimensional quantum key distribution protocols with twisted photons

Quantum key distribution is on the verge of real world applications, where perfectly secure information can be distributed among multiple parties. Several quantum cryptographic protocols have been theoretically proposed and independently realized in different experimental conditions. Here, we develop an experimental platform based on high-dimensional orbital angular momentum states of single photons that enables implementation of multiple quantum key distribution protocols with a single experimental apparatus. Our versatile approach allows us to experimentally survey different classes of quantum key distribution techniques, such as the 1984 Bennett & Brassard (BB84), tomographic protocols including the six-state and the Singapore protocol, and to investigate, for the first time, a recently introduced differential phase shift (Chau15) protocol using twisted photons. This enables us to experimentally compare the performance of these techniques and discuss their benefits and deficiencies in terms of noise tolerance in different dimensions.