Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Conference on Lasers and Electro-Optics

Witnessing Effective Entanglement over 2km of Optical Fiber

Christoffer Wittmann, Josef Urban Fürst, Carlos Wiechers, Dominique Elser, Hauke Häseler, Norbert Lütkenhaus, Gerd Leuchs

Published Jan 1, 2010• 0 citations
Publisher

Abstract

We present a continuous-variable QKD system using heterodyne detection. We experimentally determine channel characteristics and compare them to bounds of our entanglement criterion. For the first time, the local oscillator is considered in this verification.
DOI
10.1364/qels.2010.qthi4

Related papers

Witnessing effective entanglement over a 2km fiber channel

Wittmann, C., Fuerst, J., Wiechers, C. +4 more

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 measures conjugate quadratures of the light using two homodyne detectors. From the measured Q-function of the transmitted signal, we estimate the attenuation and the excess noise caused by the channel. The estimated excess noise originating from the channel and the channel attenuation including the quantum efficiency of the detection setup is investigated with respect to the detection of effective entanglement. The local oscillator is considered in the verification. We witness effective entanglement with a channel length of up to 2km. (C) 2010 Optical Society of America

•Jan 1, 2010•17 citations

Witnessing effective entanglement over a 2km fiber channel

Christoffer Wittmann, Josef Fürst, Carlos Wiechers +4 more

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 measures conjugate quadratures of the light using two homodyne detectors. From the measured Q-function of the transmitted signal, we estimate the attenuation and the excess noise caused by the channel. The estimated excess noise originating from the channel and the channel attenuation including the quantum efficiency of the detection setup is investigated with respect to the detection of effective entanglement. The local oscillator is considered in the verification. We witness effective entanglement with a channel length of up to 2 km.

arXiv:0911.3032•Optics Express•Feb 19, 2010•17 citations

Continuous-variable quantum key distribution with true local oscillator

Brian P. Williams, Bing Qi, Muneer Alshowkan +2 more

In continuous variable quantum key distribution (CV-QKD), using a truly local (not transmitted over the network) oscillator improves security. Here we report the first implementation of this CV-QKD scheme over a deployed optical fiber network.

•Jan 1, 2023•2 citations

Witnessing effective entanglement over 2km of optical fiber

Wittmann, Fürst, Wiechers +4 more

Conference on Lasers and Electro-Optics•Jan 1, 2010•0 citations

Continuous-Variable Quantum Key Distribution Over 60 km Optical Fiber With Real Local Oscillator

Adnan A. E. Hajomer, Hossein Mani, Nitin Jain +3 more

We report the first continuous-variable quantum key distribution experiment that enables the generation of secure key over a 60 km fiber channel with locally generated local oscillator. This is achieved by controlling the excess noise using machine learning for phase noise compensation while operating the system at a low modulation variance

arXiv:2205.15161•May 30, 2022•3 citations

Use of discrete modulation and a continuous wave local oscillator in a 24 km continuous variable quantum key distribution system

Xuan Quyen Dinh, Zheshen Zhang, Paul L. Voss

We implement an experimental continuous variable quantum key distribution system over 24 km of optical fiber that uses discrete signaling and a continuous wave local oscillator. A secure key rate of 3.45 kb/s was achieved.

Optical Fiber Communication Conference•Jan 1, 2010•0 citations
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 measures conjugate quadratures of the light using two homodyne detectors. From the measured Q-function of the transmitted signal, we estimate the attenuation and the excess noise caused by the channel. The estimated excess noise originating from the channel and the channel attenuation including the quantum efficiency of the detection setup is investigated with respect to the detection of effective entanglement. The local oscillator is considered in the verification. We witness effective entanglement with a channel length of up to 2km. (C) 2010 Optical Society of America
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 measures conjugate quadratures of the light using two homodyne detectors. From the measured Q-function of the transmitted signal, we estimate the attenuation and the excess noise caused by the channel. The estimated excess noise originating from the channel and the channel attenuation including the quantum efficiency of the detection setup is investigated with respect to the detection of effective entanglement. The local oscillator is considered in the verification. We witness effective entanglement with a channel length of up to 2 km.