English
Related papers

Related papers: 'Frequency-modulated' pulsed Bell setup avoids pos…

200 papers

Entanglement is an invaluable resource for fundamental tests of physics and the implementation of quantum information protocols such as device-independent secure communications. In particular, time-bin entanglement is widely exploited to…

The dispersion cancellation feature of pulses which are entangled in frequency is employed to synchronize clocks of distant parties. The proposed protocol is insensitive to the pulse distortion caused by transit through a dispersive medium.…

Quantum Physics · Physics 2009-11-07 V. Giovannetti , S. Lloyd , L. Maccone , F. N. C. Wong

Phase correlations are an under-explored vulnerability in QKD. Here, we present an experimental and simulated characterization of correlations arising from electro-optic phase encoding, over repetition rates up to the GHz level. To mitigate…

Quantum Physics · Physics 2025-09-24 Amita Gnanapandithan , Li Qian , Hoi-Kwong Lo

To guarantee the security of quantum key distribution (QKD), several assumptions on light sources must be satisfied. For example, each random bit information is precisely encoded on an optical pulse and the photon-number probability…

Quantum Physics · Physics 2020-08-07 Akihiro Mizutani , Toshihiko Sasaki , Yuki Takeuchi , Kiyoshi Tamaki , Masato Koashi

We present a new class of control pulses designed to transfer co-located ensembles without relying on frequency selectivity, thereby allowing much faster state-transitions. A geometric approach allows us to construct sequences which are…

Atomic Physics · Physics 2026-04-23 K. L. Wood , W. A. Terrano

This paper analyzes effects of time-dependence in the Bell inequality. A generalized inequality is derived for the case when coincidence and non-coincidence [and hence whether or not a pair contributes to the actual data] is controlled by…

Quantum Physics · Physics 2022-03-16 Jan-Åke Larsson , Richard Gill

Timing requirements for long-range quantum networking are driven by the necessity of synchronizing the arrival of photons, from independent sources, for Bell-state measurements. Thus, characteristics such as repetition rate and pulse…

Quantum Physics · Physics 2023-07-03 Randy Lafler , R. Nicholas Lanning

Quantum key distribution (QKD), a technology that enables perfectly secure communication, has evolved to the stage where many different protocols are being used in real-world implementations. Each protocol has its own advantages, meaning…

Quantum Physics · Physics 2018-09-14 G. L. Roberts , M. Lucamarini , J. F. Dynes , S. J. Savory , Z. L. Yuan , A. J. Shields

Bell's inequality sets a strict threshold for how strongly correlated the outcomes of measurements on two or more particles can be, if the outcomes of each measurement are independent of actions undertaken at arbitrarily distant locations.…

Quantum Physics · Physics 2022-05-24 David I. Kaiser

Quantum key distribution (QKD) systems provide a method for two users to exchange a provably secure key. Synchronizing the users' clocks is an essential step before a secure key can be distilled. Qubit-based synchronization protocols…

Quantum Physics · Physics 2021-08-11 Roderick D. Cochran , Daniel J. Gauthier

Measurement-device-independent quantum key distribution (MDI-QKD) eliminates detector side-channel attacks by relocating all measurements to an untrusted intermediate node. However, its practical implementation critically relies on…

Quantum Physics · Physics 2025-12-22 A. P. Pljonkin

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

Quantum computers, which process information encoded in quantum mechanical systems, hold the potential to solve some of the hardest computational problems. A substantial obstacle for the further development of quantum computers is the fact…

Quantum Physics · Physics 2012-11-02 Alexandre M. Souza , Gonzalo A. Álvarez , Dieter Suter

Quantum Key Distribution (QKD) allows unconditionally secure communication based on the laws of quantum mechanics rather then assumptions about computational hardness. Optimizing the operation parameters of a given QKD implementation is…

We present an algorithm to detect the time and frequency difference of independent clocks based on observation of time-correlated photon pairs. This enables remote coincidence identification in entanglement-based quantum key distribution…

Quantum Physics · Physics 2009-05-17 Caleb Ho , Antia Lamas-Linares , Christian Kurtsiefer

We apply the techniques introduced in [Kraus et. al., Phys. Rev. Lett. 95, 080501, 2005] to prove security of quantum key distribution (QKD) schemes using two-way classical post-processing as well as QKD schemes based on weak coherent…

Quantum Physics · Physics 2011-11-09 Barbara Kraus , Cyril Branciard , Renato Renner

Reasoning about Bell nonlocality from the correlations observed in post-selected data is always a matter of concern. This is because conditioning on the outcomes is a source of non-causal correlations, known as a selection bias, rising…

Quantum Physics · Physics 2021-11-17 Pawel Blasiak , Ewa Borsuk , Marcin Markiewicz

Quantum key distribution (QKD) is a secure key generation method between two distant parties by wisely exploiting properties of quantum mechanics. In QKD, experimental measurement outcomes on quantum states are transformed by the two…

Quantum Physics · Physics 2010-03-01 Chi-Hang Fred Fung , Xiongfeng Ma , H. F. Chau

The experimental implementation of the polarization encoding system is presented using weak coherent pulses at a low enough frequency. The optical pulses are generated through intensity modulation at the repetition rate of $10$ pulses/sec…

Quantum Physics · Physics 2025-06-04 Zeshan Haider

Although quantum key distribution (QKD) is theoretically secure, there is a gap between the theory and practice. In fact, real-life QKD may not be secure because component devices in QKD systems may deviate from the theoretical models…