实验双场量子密钥分布在1000公里的光纤距离上
Yang Liu1,2,3, Wei-Jun Zhang4, Cong Jiang2,3
1Hefei National Research Center for Physical Sciences at the Microscale and School of Physical Sciences, University of Science and Technology of China, Hefei 230026, China.
Physical review letters
|June 9, 2023
概括
研究人员展示了一种基于光纤的1002公里的量子密钥分配 (QKD) 系统,克服了安全密钥生成的距离限制. 这一突破推进了使用先进的光子检测和一种新的QKD协议的实用,大规模量子网络.
科学领域:
- 量子信息科学 量子信息科学
- 量子通信是一种量子通信.
- 安全的通信技术 安全的通信技术
背景情况:
- 量子密钥分布 (QKD) 基于量子力学提供了无与伦比的安全性.
- 由于光纤中的信号损失,实际的QKD受到距离限制的阻碍.
- 量子信号不能被放大,这对远距离传输构成了重大挑战.
研究的目的:
- 为了演示一个基于光纤的双场QKD系统超过1002公里.
- 为了克服当前QKD技术中的距离限制.
- 推动大规模量子网络的发展.
主要方法:
- 使用3强度发送或不发送协议.
- 实施了积极奇偶平价配对方法以提高性能.
- 开发了双频段相位估计和超低噪声超导纳米线单光子探测器.
主要成果:
- 在1002公里的纪录距离上实现了基于光纤的双场QKD.
- 使用先进的探测器将系统噪声压低到大约0.02 Hz.
- 获得的安全密钥速率为每脉冲9.53×10−12 (非对称) 和每脉冲8.75×10−12 (在952公里处具有有限大小的效应).
结论:
- 这项工作代表了实用,远程QKD的关键进步.
- 展示的系统克服了QKD应用的主要技术障碍.
- 这些发现为未来的大规模量子网络铺平了道路.
相关概念视频
01:31Energy Stored In A Coaxial Cable
1.6K
A coaxial cable consists of a central copper conductor used for transmitting signals, followed by an insulator shield, a metallic braided mesh that prevents signal interference, and a plastic layer that encases the entire assembly.
In the simplest form, a coaxial cable can be represented by two long hollow concentric cylinders in which the current flows in opposite directions. The magnetic field inside and outside the coaxial cable is determined by using Ampère's law. The magnetic...
In the simplest form, a coaxial cable can be represented by two long hollow concentric cylinders in which the current flows in opposite directions. The magnetic field inside and outside the coaxial cable is determined by using Ampère's law. The magnetic...
1.6K
01:30Propagation Speed of Electromagnetic Waves
3.5K
Electromagnetic waves are consistent with Ampere's law. Assuming there is no conduction current Ampere's law is given as:
3.5K
01:27¹H NMR: Long-Range Coupling
1.8K
The coupling interactions of nuclei across four or more bonds are usually weak, with J values less than 1 Hz. While these are usually not observed in spectra, the presence of multiple bonds along the coupling pathway can result in observable long-range coupling.
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene...
In alkenes, spin information is communicated via σ–π overlap, as seen in allylic (four-bond) and homoallylic (five-bond) couplings. These coupling interactions are stronger when the σ bond is parallel to the alkene...
1.8K