English
Related papers

Related papers: Entangled state quantum cryptography: Eavesdroppin…

200 papers

We produce two identical keys using, for the first time, entangled trinary quantum systems (qutrits) for quantum key distribution. The advantage of qutrits over the normally used binary quantum systems is an increased coding density and a…

Quantum Physics · Physics 2007-05-23 Simon Groeblacher , Thomas Jennewein , Alipasha Vaziri , Gregor Weihs , Anton Zeilinger

Device-independent quantum key distribution (DIQKD) guarantees unconditional security of secret key without making assumptions about the internal workings of the devices used. It does so using the loophole-free violation of a Bell's…

Quantum Physics · Physics 2016-05-04 Kaushik P. Seshadreesan , Masahiro Takeoka , Masahide Sasaki

We construct an entangled photon polarimeter capable of monitoring a two-qubit quantum state in real time. Using this polarimeter, we record a nine frames-per-second video of a two-photon state's transition from separability to…

Quantum Physics · Physics 2015-05-30 Joseph B. Altepeter , Neal N. Oza , Milja Medic , Evan R. Jeffrey , Prem Kumar

We show that the expectation value of squared correlations measured along random local directions is an identifier of quantum entanglement in pure states which can be directly experimentally assessed if two copies of the state were…

Quantum Physics · Physics 2015-11-18 Minh Cong Tran , Borivoje Dakic , Francois Arnault , Wieslaw Laskowski , Tomasz Paterek

With the increasing demand for secure communication in optical space networks, it is essential to develop physical-layer scalable security solutions. In this context, we present the asymptotic security analysis of a keyless quantum private…

Quantum Physics · Physics 2024-09-12 Angeles Vazquez-Castro , Andreas Winter , Hugo Zbinden

We propose a high-efficiency three-party quantum key agreement protocol, by utilizing two-photon polarization-entangled Bell states and a few single-photon polarization states as the information carriers, and we use the quantum dense coding…

Quantum Physics · Physics 2019-06-26 Wan-Ting He , Jun Wang , Tian-Tian Zhang , Faris Alzahrani , Aatef Hobiny , Tasawar Hayat , Fu-Guo Deng

Entanglement is the key feature of many-body quantum systems, and the development of new tools to probe it in the laboratory is an outstanding challenge. Measuring the entropy of different partitions of a quantum system provides a way to…

A design is given for an optimized entangling probe attacking the BB84 (Bennett-Brassard 1984) protocol of quantum key distribution and yielding maximum information to the probe for a full range of induced error rates. Probe photon…

Quantum Physics · Physics 2007-05-23 Howard E. Brandt

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

We present an entangled-state quantum cryptography system that operated for the first time in a real world application scenario. The full key generation protocol was performed in real time between two distributed embedded hardware devices,…

We report the observation of entanglement between a single trapped atom and a single photon at a wavelength suitable for low-loss communication over large distances, thereby achieving a crucial step towards long range quantum networks. To…

We investigate the practicality of the method proposed by Maciel et al. [Phys. Rev. A. 80, 032325(2009)] for detecting the entanglement of two spatial qutrits (3-dimensional quantum systems), which are encoded in the discrete transverse…

Quantum Physics · Physics 2015-05-18 G. Lima , E. S. Gómez , A. Vargas , R. O. Vianna , C. Saavedra

The theory of quantum cryptography aims to guarantee unconditional information-theoretic security against an omnipotent eavesdropper. In many practical scenarios, however, the assumption of an all-powerful adversary is excessive and can be…

Entanglement detection is one of the most conventional tasks in quantum information processing. While most experimental demonstrations of high-dimensional entanglement rely on fidelity-based witnesses, these are powerless to detect…

Entanglement represents an important resource for quantum information processing, but its generation itself requires physical resources that are limited. We propose a scheme for generating a wide class of entangled qudit-type states of…

Quantum Physics · Physics 2012-02-09 S. Ya. Kilin , A. B. Mikhalychev

With the advancement of non-classical light sources such as single-photon and entangled-photon sources, innovative microscopy based on the quantum principles has been proposed over traditional microscopy. This paper introduces the…

Quantum Physics · Physics 2025-01-08 Mousume Samad , Maki Shimizu , Yasuto Hijikata

We suggest a quantum cryptographic scheme using continuous EPR-like correlations of bright optical beams. For binary key encoding, the continuous information is discretized in a novel way by associating a respective measurement, amplitude…

Quantum Physics · Physics 2009-11-07 Ch. Silberhorn , N. Korolkova , G. Leuchs

A simplified eavesdropping-strategy for BB84 protocol in quantum cryptography (refer to quant-ph/9812022) is proposed. This scheme implements by the `indirect copying' technology. Under this scheme, eavesdropper can exactly obtain the…

Quantum Physics · Physics 2007-05-23 Guihua Zeng

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…

We present a systematic entanglement concentration protocol (ECP) for an arbitrary unknown less-entangled three-photon W state, resorting to the optical property of the quantum-dot spins inside one-sided optical microcavities. In our ECP,…

Quantum Physics · Physics 2015-11-03 Fang-Fang Du , Fu-Guo Deng
‹ Prev 1 8 9 10 Next ›