Layered quantum key distribution
Matej Pivoluska, Marcus Huber, Mehul Malik · Physical Review A · 2018
We introduce a family of quantum key distribution protocols for distributing shared random keys within a network of $n$ users. The advantage of these protocols is that any possible key structure needed within the network, including broadcast keys shared among subsets of users, can be implemented by using a particular multipartite high-dimensionally entangled quantum state. This approach is more efficient in the number of quantum channel uses than conventional quantum key distribution using bipartite links. Additionally, multipartite high-dimensional quantum states are becoming readily available in quantum photonic labs, making the proposed protocols implementable using current technology.