English
Related papers

Related papers: Modified E91 protocol demonstration with hybrid en…

200 papers

We present a quantum key distribution (QKD) system based on polarisation entanglement for use in telecom fibers. A QKD exchange up to 50km was demonstrated in the laboratory with a secure key rate of 550 bit/s. The system is compact,…

We consider a generalisation of Ekert's entanglement-based quantum cryptographic protocol where qubits are replaced by qu$N$its (i.e., N-dimensional systems). In order to study its robustness against optimal incoherent attacks, we derive…

Quantum Physics · Physics 2009-11-10 Thomas Durt , Dagomir Kaszlikowski , Jing-Ling Chen , L. C. Kwek

Multipartite entanglement enables secure group key distribution among multiple users while providing immunity against hacking attacks targeting source devices, thereby realizing source-independent quantum conference key agreement (SI-QCKA).…

Quantum Physics · Physics 2025-12-24 Wen-Ji Hua , Yi-Ran Xiao , Yu Bao , Hua-Lei Yin , Zeng-Bing Chen

One of the main requirements to achieve reliable quantum communications are on-demand sources of highly entangled photon pairs, and semiconductor quantum dots have emerged as prominent candidates to satisfy the necessary conditions of…

In state-of-the-art quantum key distribution (QKD) systems, the main limiting factor in increasing the key generation rate is the timing resolution in detecting photons. Here, we present and experimentally demonstrate a strategy to overcome…

Quantum Physics · Physics 2021-07-29 Johannes Pseiner , Lukas Achatz , Lukas Bulla , Martin Bohmann , Rupert Ursin

We present a scalable star-shaped quantum key distribution (QKD) optical fiber network. We use wavelength-division demultiplexing (WDM) of broadband photon pairs to establish key exchange between multiple pairs of participants…

Quantum key distribution provides a promising solution for sharing secure keys between two distant parties with unconditional security. Nevertheless, quantum key distribution is still severely threatened by the imperfections of devices. In…

Quantum Physics · Physics 2023-08-22 Shan-Feng Shao , Xiao-Yu Cao , Yuan-Mei Xie , Jie Gu , Wen-Bo Liu , Yao Fu , Hua-Lei Yin , Zeng-Bing Chen

Quantum key distribution (QKD) with deterministic single photon sources has been demonstrated over intercity fiber and free-space channels. The previous implementations relied mainly on polarization encoding schemes, which are susceptible…

We present a proof-of-principle experimental demonstration of a reconfigurable entanglement distribution scheme utilizing a poled fiber-based source of broadband polarization-entangled photon pairs and dense wavelength-division…

Quantum Physics · Physics 2019-01-18 E. Y. Zhu , C. Corbari , A. V. Gladyshev , P. G. Kazansky , H. K. Lo , L. Qian

The study of quantum cryptography and quantum non-locality have traditionnally been based on two-level quantum systems (qubits). In this paper we consider a generalisation of Ekert's cryptographic protocol [Ekert] where qubits are replaced…

Quantum Physics · Physics 2009-11-07 Thomas Durt , Nicolas J. Cerf , Nicolas Gisin , Marek Zukowski

Quantum key distribution (QKD) is a cryptographic protocol to enable two parties to share a secure key string, which can be used in one-time pad cryptosystem. There has been an ongoing surge of interest in implementing long-haul…

Quantum Physics · Physics 2022-08-22 Sourav Chatterjee , Kaumudibikash Goswami , Rishab Chatterjee , Urbasi Sinha

We report a fully fibered source emitting cross time-bin entangled photons at 1540 nm from type-II spontaneous parametric down conversion. Compared to standard time-bin entanglement realizations, the preparation interferometer requires no…

Quantum Physics · Physics 2015-03-20 A. Martin , F. Kaiser , A. Vernier , A. Beveratos , V. Scarani , S. Tanzilli

We present a quantum repeater protocol for distributing entanglement over long distances, where a dedicated communication stage enables trial rates not limited by the travel time between repeater nodes. To accomplish this, each node…

Quantum Physics · Physics 2025-04-25 Adam Kinos , Andreas Walther , Stefan Kröll , Lars Rippe

By realizing a quantum cryptography system based on polarization entangled photon pairs we establish highly secure keys, because a single photon source is approximated and the inherent randomness of quantum measurements is exploited. We…

Quantum Physics · Physics 2009-10-31 Thomas Jennewein , Christoph Simon , Gregor Weihs , Harald WeinfurterD , Anton Zeilinger

Entanglement-based quantum key distribution (QKD) is an essential ingredient in quantum communication, owing to the property of source-independent security and the potential on constructing large-scale quantum communication networks.…

Quantum Physics · Physics 2022-12-07 Jingyuan Liu , Zhihao Lin , Dongning Liu , Xue Feng , Fang Liu , Kaiyu Cui , Yidong Huang , Wei Zhang

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

Entanglement distribution based on time-bin qubits is an attractive option for emerging quantum networks. We demonstrate a 4.09 GHz repetition rate source of photon pairs entangled across early and late time bins separated by 80 ps.…

Encoding quantum information in photonic time-bin states is typically considered impractical for moving free-space quantum communication due to the difficulties with phase stabilization of distant quantum time-bin interferometers and…

We have designed and realized a prototype that implements a continuous-variable quantum key distribution protocol based on coherent states and reverse reconciliation. The system uses time and polarization multiplexing for optimal…

In recent years quantum information research has lead to the discovery of a number of remarkable new paradigms for information processing and communication. These developments include quantum cryptography schemes that offer unconditionally…