Shihan Sajeed,1,2,* Igor Radchenko,3 Sarah Kaiser,1,4 Jean-Philippe Bourgoin,1,4 Anna Pappa,5 Laurent Monat,6 Matthieu Legré,6 and Vadim Makarov1,4,2 1Institute for Quantum Computing, University of Waterloo, Waterloo, ON, N2L 3G1 Canada 2Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, ON, N2L 3G1 Canada 3General Physics Institute, Russian Academy of Sciences...

The security of quantum key distribution with sub-Poisson light sources is investigated. It is shown that a quantitative analysis of the security of such sources requires only two measured values, the efficiency and second-order correlation. These two numbers represent figures of merit, which characterize the performance of such light sources. We show that sub-Poisson light sources can offer si...

We propose the adaptive multicarrier quadrature division–multiuser quadrature allocation (AMQD-MQA) multiple access technique for continuous-variable quantum key distribution (CVQKD). The MQA scheme is based on the AMQD modulation, which granulates the inputs of the users into Gaussian subcarrier continuous-variables (CVs). The subcarrier coherent states formulate Gaussian sub-channels from the...

We introduce the multidimensional manifold extraction for multicarrier continuousvariable (CV) quantum key distribution (QKD). The manifold extraction utilizes the resources that are injected into the transmission by the additional degrees of freedom of the multicarrier modulation. We demonstrate the results through the AMQD (adaptive multicarrier quadrature division) scheme, which granulates t...

Quantum Key Distribution (QKD) networks are of much interest due to their capacity of providing extremely high security keys to network participants. Most QKD network studies so far focus on trusted models where all the network nodes are assumed to be perfectly secured. This restricts QKD networks to be small. In this paper, we first develop a novel model dedicated to large-scale QKD networks, ...

In 2005, trace distance between an ideal quantum state to be distributed and an actually distributed quantum state was introduced as a valid security measure of Quantum Key Distribution (QKD) by R. Renner et al., then it has been perceived that the trace can be interpreted as a maximum failure probability of QKD. While such a perspective has been widely accepted, H. P. Yuen and O. Hirota have b...

The Quantum Key Distribution (QKD) protocol BB84 has been proven secure against several important types of attacks: the collective attacks and the joint attacks. Here we analyze the security of a modified BB84 protocol, for which information is sent only in the z basis while testing is done in both the z and the x bases, against collective attacks. The proof follows the framework of a previous ...

We consider the problem of secure key distribution among n trustful agents: the goal is to distribute an identical random bit-string among the n agents over a noisy channel such that eavesdroppers learn little about it. We study the general situation where the only resources required are secure bipartite key distribution and authenticated classical communication. Accordingly, multipartite quant...

Quantum key distribution is among the foremost applications of quantum mechanics, both in terms of fundamental physics and as a technology on the brink of commercial deployment. Starting from principal schemes and initial proofs of unconditional security for perfect systems, much effort has gone into providing secure schemes which can cope with numerous experimental imperfections unavoidable in...