English
Related papers

Related papers: Improvement of two-way continuous-variable quantum…

200 papers

A multi-user quantum key distribution protocol is proposed with single particles and the collective eavesdropping detection strategy on a star network. By utilizing this protocol, any two users of the network can accomplish quantum key…

Quantum Physics · Physics 2015-07-21 Wei Huang , Qiao-Yan Wen , Bin Liu , Fei Gao

Quantum key distribution (QKD) and quantum message encryption protocols promise a secure way to distribute information while detecting eavesdropping. However, current protocols may suffer from significantly reduced eavesdropping protection…

Quantum Physics · Physics 2025-05-27 Nicholas J. C. Papadopoulos , Kirby Linvill

We describe the experimental test of a quantum key distribution performed with a two-way protocol without using entanglement. An individual incoherent eavesdropping is simulated and induces a variable amount of noise on the communication…

Quantum Physics · Physics 2009-09-14 A. Cere' , M. Lucamarini , G. Di Giuseppe , P. Tombesi

We consider two-way continuous-variable quantum key distribution, studying its security against general eavesdropping strategies. Assuming the asymptotic limit of many signals exchanged, we prove that two-way Gaussian protocols are immune…

Quantum Physics · Physics 2017-05-09 Carlo Ottaviani , Stefano Pirandola

Linear quantum amplifiers are indispensable tools for quantum technologies, yet their performance is fundamentally limited by quantum noise, precluding any signal-to-noise ratio (SNR) enhancement unless supplemented by post-selection or…

Quantum Physics · Physics 2026-03-13 Ya-Long Ren , Rong-Teng Cao , Sheng-Li Ma , Ren Zhang , Fu-Li Li , Franco Nori , Peng-Bo Li

We propose efficient-phase-encoding protocols for continuous-variable quantum key distribution using coherent states and postselection. By these phase encodings, the probability of basis mismatch is reduced and total efficiency is…

Quantum Physics · Physics 2008-09-29 Ryo Namiki , Takuya Hirano

Quantum metrology is supposed to significantly improve the precision of parameter estimation by utilizing suitable quantum resources. However, the predicted precision can be severely distorted by realistic noises. Here, we propose a…

Quantum Physics · Physics 2023-02-15 Yue Zhai , Xiaodong Yang , Kai Tang , Xinyue Long , Xinfang Nie , Tao Xin , Dawei Lu , Jun Li

We propose a continuous variable quantum key distribution protocol based on discrete modulation of eight-state coherent states. We present a rigorous security proof against the collective attacks considering both of realistic lossy, noisy…

Quantum Physics · Physics 2010-06-23 A. Becir , F. A. A. El-Orany , M. R. B. Wahiddin

We investigate quantum key distribution (QKD) in optical multiple-input-multiple-output (MIMO) settings. Such settings can prove useful in dealing with harsh channel conditions as in, e.g., satellite-based QKD. We study a $2\times2$ setting…

Quantum Physics · Physics 2023-08-23 Shradhanjali Sahu , Ahmed Lawey , Mohsen Razavi

We describe a continuous variables coherent states quantum key distribution system working at 1550 nm, and entirely made of standard fiber optics and telecom components, such as integrated-optics modulators, couplers and fast InGaAs…

Quantum Physics · Physics 2007-05-23 Jérôme Lodewyck , Thierry Debuisschert , Rosa Tualle-Brouri , Philippe Grangier

In this work we study the use of noiseless attenuation and noiseless amplification, in terms of multi-mode Continuous-Variable (CV) Quantum Key Distribution (QKD) over satellite-to-ground channels. We propose an improved multi-mode CV-QKD…

Quantum Physics · Physics 2021-03-11 Mingjian He , Robert Malaney , Benjamin Burnett

We present a fiber-based continuous-variable quantum key distribution system. In the scheme, a quantum signal of two non-orthogonal weak optical coherent states is sent through a fiber-based quantum channel. The receiver simultaneously…

The security proof of continuous variable quantum key distribution(CV QKD) based on two assumptions that the eavesdropper can neither act on the local oscillator nor control Bob's beam splitter. These assumptions maybe invalid in practice…

Quantum Physics · Physics 2013-05-14 Jing-Zheng Huang , Zhen-Qiang Yin , Shuang Wang , Hong-Wei Li , Wei Chen , Guan-Can Guo , Zheng-Fu Han

In this paper we report a continuous-variable quantum key distribution protocol using multimode coherent states generated on subcarrier frequencies of the optical spectrum. To detect the quadrature components of bosonic field we propose a…

Semi-quantum key distribution protocols are designed to allow two parties to establish a shared secret key, secure against an all-powerful adversary, even when one of the users is restricted to measuring and preparing quantum states in one…

Quantum Physics · Physics 2019-11-15 Omar Amer , Walter O. Krawec

In the recent decade, it has been discovered that QKD systems are extremely vulnerable to side-channel attacks. In particular, by exploiting the internal working knowledge of practical detectors, it is possible to bring them to an operating…

Quantum Physics · Physics 2015-02-02 Charles Ci Wen Lim , Nino Walenta , Matthieu Legre , Nicolas Gisin , Hugo Zbinden

We propose a linear-optical scheme for an efficient amplification of a photonic qubit based on interaction of the signal mode with a pair of entangled ancillae. In contrast to a previous proposal for qubit amplifier by Gisin et al., [Phys…

We present a pilot-assisted coherent intradyne reception methodology for CV-QKD with true local oscillator. An optically phase-locked reference tone, prepared using carrier-suppressed optical single-sideband modulation, is multiplexed in…

We study the robustness of quantum key distribution protocols using discrete or continuous variables to the channel noise. We introduce the model of such noise based on coupling of the signal to a thermal reservoir, typical for…

Quantum Physics · Physics 2017-06-12 Mikołaj Lasota , Radim Filip , Vladyslav C. Usenko

We prove the unconditional security of an entanglement-based quantum-key-distribution protocol using detectors that respond to multiple modes of light and cannot distinguish between one from two or more photons. Even with such practical…

Quantum Physics · Physics 2008-04-08 Masato Koashi , Yoritoshi Adachi , Takashi Yamamoto , Nobuyuki Imoto