English
Related papers

Related papers: Security of Decoy-State Protocols for General Phot…

200 papers

We present a new protocol for practical quantum cryptography, tailored for an implementation with weak coherent pulses. The key is obtained by a very simple time-of-arrival measurement on the data line; an interferometer is built on an…

We present a finite-size security proof for generic quantum key distribution protocols against independent and identically distributed collective attacks and extend it to coherent attacks using the postselection technique. This work…

Quantum Physics · Physics 2025-02-11 Lars Kamin , Devashish Tupkary , Norbert Lütkenhaus

In the decoy quantum key distribution, we show that a smaller decoy intensity gives a better key generation rate in the asymptotic setting when we employ only one decoy intensity and the vacuum pulse. In particular, the counting rate of…

Quantum Physics · Physics 2016-09-28 Masahito Hayashi

We describe a cryptographic protocol in which Wheeler's delayed choice experiment is used to generate the key distribution. The protocol, which uses photons polarized only along one axis, is secure against general attacks.

Quantum Physics · Physics 2009-10-28 M. Ardehali

We present a protocol for quantum cryptography in which the data obtained for mismatched bases are used in full for the purpose of quantum state tomography. Eavesdropping on the quantum channel is seriously impeded by requiring that the…

We investigate limitations imposed by sequential attacks on the performance of differential-phase-shift quantum key distribution protocols that use pulsed coherent light. In particular, we analyze two sequential attacks based on unambiguous…

Quantum Physics · Physics 2013-08-21 Marcos Curty , Lucy Liuxuan Zhang , Hoi-Kwong Lo , Norbert Lütkenhaus

We study the measurement device independent quantum key distribution (MDI-QKD) in practice with limited resource, when there are only 3 different states in implementing the decoy-state method. We present a more tightened explicit formula to…

Quantum Physics · Physics 2014-01-08 Z. -W. Yu , Y. -H. Zhou , X. -B. Wang

Device-independent quantum cryptographic schemes aim to guarantee security to users based only on the output statistics of any components used, and without the need to verify their internal functionality. Since this would protect users…

Quantum Physics · Physics 2013-08-07 Jonathan Barrett , Roger Colbeck , Adrian Kent

A quantum key distribution protocol based on time coding uses delayed one photon pulses with minimum time-frequency uncertainty product. Possible overlap between the pulses induces an ambiguous delay measurement and ensures a secure key…

Quantum Physics · Physics 2007-05-23 Thierry Debuisschert , William Boucher

Decoy states have recently been proposed as a useful method for substantially improving the performance of quantum key distribution protocols when a coherent state source is used. Previously, data post-processing schemes based on one-way…

Quantum Physics · Physics 2016-08-16 Xiongfeng Ma , Chi-Hang Fred Fung , Frédéric Dupuis , Kai Chen , Kiyoshi Tamaki , Hoi-Kwong Lo

The use of linearly independent signal states in realistic implementations of quantum key distribution (QKD) enables an eavesdropper to perform unambiguous state discrimination. We explore quantitatively the limits for secure QKD imposed by…

Quantum Physics · Physics 2009-10-31 Miloslav Dusek , Mika Jahma , Norbert Lütkenhaus

In this paper we present quantum key distribution protocol that, instead of single qubits, uses mesoscopic coherent states of light $|\alpha\rangle$ to encode bit values of a randomly generated key. Given the reference value…

Quantum Physics · Physics 2017-05-04 G. A. Barbosa , J. van de Graaf , P. Mateus , N. Paunković

In single-qubit quantum secret sharing, a secret is shared between N parties via manipulation and measurement of one qubit at a time. Each qubit is sent to all N parties in sequence; the secret is encoded in the first participant's…

Quantum Physics · Physics 2011-09-12 P. Scherpelz , R. Resch , D. Berryrieser , T. W. Lynn

Quantum key distribution is a way to distribute secret keys to distant users with information theoretic security and key rates suitable for real-world applications. Its rate-distance figure, however, is limited by the natural loss of the…

Quantum Physics · Physics 2018-09-12 Kiyoshi Tamaki , Hoi-Kwong Lo , Wenyuan Wang , Marco Lucamarini

The use of quantum bits (qubits) in cryptography holds the promise of secure cryptographic quantum key distribution schemes. Unfortunately, the implemented schemes can be totally insecure. We provide a thorough investigation of security…

Quantum Physics · Physics 2009-10-31 Gilles Brassard , Norbert Lütkenhaus , Tal Mor , Barry C. Sanders

Weak coherent states as a photon source for quantum cryptography have limit in secure data rate and transmission distance because of the presence of multi-photon events and loss in transmission line. Two-photon events in a coherent state…

Quantum Physics · Physics 2009-11-11 Y. J. Lu , Luobei Zhu , Z. Y. Ou

We propose a method to prepare different non-Poissonian signal pulses from sources of Poissonian photon number distribution using only linear optical elements and threshold photon detectors. This method allows a simple passive preparation…

Quantum Physics · Physics 2015-05-14 Marcos Curty , Tobias Moroder , Xiongfeng Ma , Norbert Lütkenhaus

I prove the security of quantum key distribution against individual attacks for realistic signals sources, including weak coherent pulses and downconversion sources. The proof applies to the BB84 protocol with the standard detection scheme…

Quantum Physics · Physics 2009-10-31 Norbert Lütkenhaus

We propose a practical decoy state method with heralded single photon source for quantum key distribution (QKD). In the protocol, 3 intensities are used and one can estimate the fraction of single-photon counts. The final key rate over…

Quantum Physics · Physics 2013-05-29 Qin Wang , Xiang-Bin Wang , Guang-Can Guo

We study the possible application of the decoy state method on a basic two way quantum key distribution (QKD) scheme to extend its distance. Noting the obvious advantage of such a QKD scheme in allowing for single as well as double photon…

Quantum Physics · Physics 2015-05-19 J. S. Shaari , Iskandar Bahari , Sellami Ali