# Continuous-variable QKD over 50 km commercial fiber

@article{Zhang2019ContinuousvariableQO, title={Continuous-variable QKD over 50 km commercial fiber}, author={Yichen Zhang and Zhengyu Li and Ziyang Chen and Christian Weedbrook and Yijia Zhao and Xiangyu Wang and Chunchao Xu and Xiaoxiong Zhang and Zhenya Wang and Mei Li and Xueying Zhang and Ziyong Zheng and Binjie Chu and Xinyu Gao and Nan Meng and Weiwen Cai and Zhen Wang and Gan Wang and Song Yu and Hong Guo}, journal={Quantum Science and Technology}, year={2019}, volume={4} }

The continuous-variable version of quantum key distribution (QKD) offers the advantages (over discrete-variable systems) of higher secret key rates in metropolitan areas, as well as the use of standard telecom components that can operate at room temperature. An important step in the real-world adoption of continuous-variable QKD is the deployment of field tests over commercial fibers. Here we report two different field tests of a continuous-variable QKD system through commercial fiber networks…

## 122 Citations

### Long-Distance Continuous-Variable Quantum Key Distribution over 202.81 km of Fiber.

- PhysicsPhysical review letters
- 2020

This record-breaking implementation of the continuous-variable quantum key distribution doubles the previous distance record and shows the road for long-distance and large-scale secure quantum key Distribution using room-temperature standard telecom components.

### Continuous-variable quantum key distribution under strong channel polarization disturbance

- PhysicsPhysical Review A
- 2020

In a commercial fiber-based quantum key distribution (QKD) system, the state of polarization (SOP) of the optical fields is inevitably disturbed by random birefringence of the standard single-mode…

### Digital synchronization for continuous-variable quantum key distribution

- Computer Science, PhysicsQuantum Science and Technology
- 2022

This work proposes a digital synchronization procedure for a modern CV-QKD system with locally generated local oscillator for coherent reception that is modulation format independent and paves the way for cost-effective QKD solutions that can adapt rapidly to changing environmental conditions.

### Long-distance continuous-variable measurement-device-independent quantum key distribution with postselection

- Computer SciencePhysical Review Research
- 2020

A robust scheme for long-distance continuous-variable (CV) measurement-device-independent (MDI) quantum key distribution (QKD) in which post-selection is employed between distant parties communicating through the medium of an untrusted relay to overcome the rate-distance limitations of previously proposed CV MDI protocols.

### Experimental continuous-variable quantum key distribution using a thermal source

- Computer ScienceNew Journal of Physics
- 2021

Due to the avoidance of modulators and QRNG, the passive state encoding scheme provides a promising direction of applicable high-speed, chip-based and even sunlight-based CVQKD with less cost and complexity.

### Field trial of a finite-key quantum key distribution system in the Florence metropolitan area

- Physics
- 2019

In-field demonstrations in real-world scenarios boost the development of a rising technology towards its integration in existing infrastructures. Although quantum key distribution (QKD) devices are…

### Field trial of a three-state quantum key distribution scheme in the Florence metropolitan area

- PhysicsEPJ Quantum Technology
- 2019

A simple, practical and efficient QKD scheme with finite-key analysis, performed over a 21 dB-losses fiber link installed in the metropolitan area of Florence (Italy), and coexistence of quantum and weak classical communication.

### Boosting higher secret key rate in quantum key distribution over mature telecom components

- Physics, Computer Science
- 2021

The results represent the achieved highest secret key generation rate for quantum key distribution using continuous variables at a standard telecom wavelength, and breaks the isolation between quantum communication and classical optical communication in terms of components, and opens the way to a high-speed and cost-effective formation of metropolitan quantum secure communication networks.

### Practical source monitoring for continuous-variable quantum key distribution

- Computer Science
- 2021

By using the practical source monitoring scheme the impact of the RIN can be modeled and monitored in real time to circumvent an overestimated secret key rate and lowers the system complexity thus is suitable for widespread application.

### Phase-Matching Continuous-Variable Measurement-Device-Independent Quantum Key Distribution

- Computer Science, PhysicsSymmetry
- 2022

This work proposes a CV-MDI-QKD protocol by encoding the key information into matched discrete phases of two groups of coherent states, which decreases the required detection efficiency for ideally asymmetric cases, and makes it possible to practically achieve secure key distribution with current low-efficiency homodyne detections.

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