Abstract. Quantum Key Distribution (QKD) refers to specific quantum strategies which permit the secure distribution of a key between two parties that wish to communicate secretly. Quantum Cryptography has proven unconditionally secure in ideal scenarios and has been successfully implemented using quantum states with finite (discrete) as well as infinite (continuous) degrees of freedom. In here,...

A quantum key distribution protocol based on entanglement swapping is proposed. Through choosing particles by twos from the sequence and performing Bell measurements, two communicators can detect eavesdropping and obtain the secure key. Because the two particles measured together are selected out randomly, we need neither alternative measurements nor rotations of the Bell states to obtain secur...

The theoretical Quantum Key-Distribution scheme of Bennett and Brassard (BB84) has been proven secure against very strong attacks including the collective attacks and the joint attacks. Though the latter are the most general attacks, collective attacks are much easier to analyze, yet, they are conjectured to be as informative to the eavesdropper. Thus, collective attacks are likely to be useful...

During the 25 years of existence of the first protocol for Quantum Key Distribution, much has been said and expected of what came to be termed as Quantum Cryptography. After all this time, much progress has been done but also the reality check and analysis that naturally comes with maturity is underway. A new panorama is emerging, and the way in which the challenges imposed by market requiremen...

Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon 305-701, Korea School of Computational Sciences, Korea Institute for Advanced Study, 207-43 Cheongryangri-dong, Dongdaemun-gu, Seoul 130-012, Korea Department of Physics and Astronomy, Hunter College of The City University of New York, 695 Park Avenue, New York, NY 10065 Department of Energy Resources Development...

Ramij Rahaman, 2, ∗ Matthew G. Parker, † Piotr Mironowicz, 5, ‡ and Marcin Paw lowski § Department of Mathematics, University of Allahabad, Allahabad 211002, U.P., India Institute of Theoretical Physics & Astrophysics, University of Gdańsk, 80-952 Gdańsk, Poland Department of Informatics, University of Bergen, Post Box-7803, 5020, Bergen, Norway Department of Algorithms and System Modelling, Fa...

We show how to calculate the fraction of single-photon counts of the 3-intensity decoy-state quantum cryptography faithfully with both statistical fluctuations and source errors. Our results rely only on the bound values of a few parameters of the states of pulses. 6 Author to whom any correspondence should be addressed. New Journal of Physics 11 (2009) 075006 1367-2630/09/075006+17$30.00 © IOP...

We propose a new Quantum Key Distribution method in which Alice sends pairs of qubits to Bob; each is in one of four possible states. Bob uses one qubit to generate a secure key and the other to generate an auxiliary key. For each pair he randomly decides which qubit to use for which key. The auxiliary key has to be added to Bob’s secure key in order to match Alice’s secure key. This scheme pro...

The use of decoy states enhances the performance of practical quantum key distribution systems significantly by monitoring the quantum channel in a more detailed way. While active modulation of the intensity of the pulses is an effective way of preparing decoy states in principle, in practice passive preparation might be desirable in some scenarios. Known passive methods involve parametric down...

The phenomenon of quantum erasure has long intrigued physicists, but has surprisingly found limited practical application. Here, we propose a protocol for quantum key distribution (QKD) based on quantum erasure, promising inherent security against detector attacks. We particularly demonstrate its security against a powerful detector-blinding attack.