This article will explore the design and implementation of quantum networks in space
integrated with quantum networks on Earth. We propose a three-layer approach, involving …

Tremendous progress in experimental quantum optics during the past decades enabled the
advent of quantum technologies, one of which is quantum communication. Aimed at novel …

Photon subtraction can enhance entanglement, which for pure states induces a decrease in
the purity of reduced states. In contrast, by analyzing the purities of Gaussian states before …

Typically practical realizations of discrete-variable quantum key distribution (QKD) protocols,
based on exchanging single-photon signals between the trusted parties, can provide its …

We address the efficiency and robustness of quantum key distribution (QKD) based on
entangled states in conditions of noisy quantum channels. We consider schemes based on …

The constraints of present supercomputers in addressing exponentially intricate problems
are apparent, as these jobs sometimes necessitate hundreds or even thousands of years …