首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Decoy state method quantum key distribution (QKD) is one of the promising practical solutions for BB84 QKD with coherent light pulses. The number of data-set size in practical QKD protocol is always finite, which will cause statistical fluctuations. In this paper, we apply absolutely statistical fluctuation to amend the yield and error rate of the quantum state. The relationship between exchanged number of quantum signals and key generation rate is analyzed in our simulation, which offers a useful reference for experiment.  相似文献   

2.
焦荣珍  张弨  马海强 《物理学报》2011,60(11):110303-110303
文章通过比较主动诱惑态和被动诱惑态的特性,假设所有可测量都围绕渐近值上下波动,得到相应变量的偏离量,采用标准误差法分析实用光源条件下,有限脉冲数编码对密钥生成率和传输距离的影响,比较了主动诱惑态、被动诱惑态 、无限长时间极限情况和不同量子效率条件下密钥生成率随传输距离的变化关系,为实用的量子密钥分配实验提供了重要的理论参数.关键词:诱惑态量子密钥分配统计涨落  相似文献   

3.
诱惑态量子密钥分配系统中统计涨落的研究   总被引:1,自引:0,他引:1  
焦荣珍  唐少杰  张弨 《物理学报》2012,61(5):50302-050302
针对实用的量子密钥分配(QKD)系统是基于强衰减的弱激光脉冲作为单光子源, 光子数分束攻击极大限制了通信双方在非理想条件下QKD的传输距离和密钥生成率,采用大数定律对诱惑态协议中单光子的计数率、单光子增益和误码率分别进行统计涨落分析, 利用双诱惑态比较了1310 nm和1550 nm条件下,编码脉冲的长度为(N = 106-N = 1012)实际QKD协议中密钥的生成率与安全传输距离之间的关系、安全传输距离随编码长度的变化的关系, 得出脉冲编码长度增大到N = 1012时,密钥的最大安全传输距离为135 km.  相似文献   

4.
东晨  赵尚弘  张宁  董毅  赵卫虎  刘韵 《物理学报》2014,63(20):200304-200304
刻画了奇相干光源的光子数分布特征,研究了奇相干光源下诱骗态测量设备无关量子密钥分配系统的密钥生成率与安全传输距离的关系,推导了奇相干光源下的计数率下界和误码率上界.仿真结果表明,奇相干光源光子数分布中多光子脉冲的比例低于弱相干光,可以有效提高诱骗态测量设备无关密钥分配系统的最大安全通信距离,为实用的量子密钥分配实验提供了重要的理论参数.  相似文献   

5.
焦荣珍  丁天  王文集  马海强 《物理学报》2013,62(18):180302-180302
通过比较被动系统与主动系统的特性, 得出可信光源、不可信光源主动系统和不可信光源被动系统的密钥生成率随距离的变化关系; 采用标准误差分析法, 得到相应变量的偏离量; 基于诱骗态方案分析不可信光源被动系统暗计数率和光源强度参数波动对系统安全特性的影响, 得出在1310 nm 和1550 nm通信窗口下, 系统最大安全通信距离范围分别为[73.2 km, 96.5 km] 和[104.5 km, 137.9 km]. 这可为实用量子通信实验提供重要的理论参数.关键词:量子密钥分配不可信光源被动系统统计波动  相似文献   

6.
         下载免费PDF全文
陈明娟  刘翔 《中国物理 B》2011,20(10):100305-100305
The most severe problem of a two-way \"plug-and-play\" (p & p) quantum key distribution system is that the source can be controlled by the eavesdropper. This kind of source is defined as an üntrusted source\". This paper discusses the effects of the fluctuation of internal transmittance on the final key generation rate and the transmission distance. The security of the standard BB84 protocol, one-decoy state protocol, and weak+vacuum decoy state protocol, with untrusted sources and the fluctuation of internal transmittance are studied. It is shown that the one-decoy state is sensitive to the statistical fluctuation but weak+vacuum decoy state is only slightly affected by the fluctuation. It is also shown that both the maximum secure transmission distance and final key generation rate are reduced when Alice's laboratory transmittance fluctuation is considered.  相似文献   

7.
         下载免费PDF全文
Wen-Ting Li 《中国物理 B》2022,31(5):50310-050310
The transmission loss of photons during quantum key distribution (QKD) process leads to the linear key rate bound for practical QKD systems without quantum repeaters. Phase matching quantum key distribution (PM-QKD) protocol, an novel QKD protocol, can overcome the constraint with a measurement-device-independent structure, while it still requires the light source to be ideal. This assumption is not guaranteed in practice, leading to practical secure issues. In this paper, we propose a modified PM-QKD protocol with a light source monitoring, named PM-QKD-LSM protocol, which can guarantee the security of the system under the non-ideal source condition. The results show that our proposed protocol performs almost the same as the ideal PM-QKD protocol even considering the imperfect factors in practical systems. PM-QKD-LSM protocol has a better performance with source fluctuation, and it is robust in symmetric or asymmetric cases.  相似文献   

8.
9.
    
Statistical fluctuations are unavoidable in realistic quantum key distribution (QKD) due to finite-size effect. Based on the four-intensity proposal on measurement-device-independent QKD (MDI-QKD) in[Phys. Rev. A 93 (2016) 042324], we particularly analyze the scenario that only three intensities are used, namely a three-intensity decoy-state MDI-QKD with biased basis choice. After performing full parameter optimization method, simulations results demonstrate that this scenario can obtain distinct enhancement compared with the conventional unbiased threeintensity decoy-state method, e.g. Xu et al.'s[Phys. Rev. A 89 (2014) 052333]. Furthermore, results also show that it works more efficiently by using HSPS than using WCS at longer transmission distance.  相似文献   

10.
         下载免费PDF全文
刘康  李剑  朱建荣  张春梅  王琴 《中国物理 B》2017,26(12):120302-120302
Reference-frame-independent quantum key distribution(RFI QKD) can generate secret keys without the alignment of reference frames, which is very robust in real-life implementations of QKD systems. However, the performance of decoystate RFI QKD with both source errors and statistical fluctuations is still missing until now. In this paper, we investigate the performance of decoy-state RFI QKD in practical scenarios with two kinds of light sources, the heralded single photon source(HSPS) and the weak coherent source(WCS), and also give clear comparison results of decoy-state RFI QKD with WCS and HSPS. Simulation results show that the secret key rates of decoy-state RFI QKD with WCS are higher than those with HSPS in short distance range, but the secret key rates of RFI QKD with HSPS outperform those with WCS in long distance range.  相似文献   

11.
偏振稳定控制下的量子密钥分发   总被引:2,自引:0,他引:2  
陈杰  黎遥  吴光  曾和平 《物理学报》2007,56(9):5243-5247
由于长距离单模光纤传输中存在的双折射效应会引起偏振随机抖动,光纤中利用偏振编码进行量子密钥分发一直难以实现.利用光子计数分析光纤中的偏振变化情况,并通过反馈控制的方式补偿偏振变化,从而实现了基于BB84协议的偏振编码长时间稳定的量子密钥分发实验,传输距离为100km.关键词:量子密钥分发偏振反馈控制单光子探测偏振随机抖动  相似文献   

12.
    
This paper proposes a new semi‐quantum key distribution protocol, allowing two “classical” participants without sophisticated quantum capability to establish a shared secret key under an untrusted third party (a quantum server). The proposed protocol is free from several well‐known attacks. Furthermore, the efficiency is better than the existing three‐party SQKD protocol in which the classical participants must have the quantum measurement capability.  相似文献   

13.
    
The semiquantum techniques have been explored recently to bridge the classical communications and the quantum communications.In this paper,we present one scheme to distribute the messages from one quantum participate to one weak quantum participate who can only measure the quantum states.It is proved to be robust by combining the classical coding encryption,quantum coding and other quantum techniques.  相似文献   

14.
  总被引:1,自引:0,他引:1  
A deterministic quantum key distribution scheme using two non-orthogonal entangled states is proposed.In the proposed scheme,communicators share key information by exchanging one travelling photon with two random and secret polarization angles.The security of the distributed key is guaranteed by three checking phases in three-way channel and the communicators' secret polarization angles.  相似文献   

15.
         下载免费PDF全文
Twin-field quantum key distribution(TF-QKD) is a disruptive innovation which is able to overcome the rate-distance limit of QKD without trusted relays. Since the proposal of the first TF-QKD protocol, theoretical and experimental breakthroughs have been made to enhance its ability. However, there still exist some practical issues waiting for settlement. In this paper, we examine the performances of asymmetric TF-QKD protocol with unstable light sources and limited data sizes. The statistical fluctuations of the parameters are estimated employing Azuma's inequality. Through numerical simulations, we compare the secret key rates of the asymmetric TF-QKD protocol with different data sizes and variant intensity fluctuation magnitudes. Our results demonstrate that both statistical and intensity fluctuations have significant impacts on the performance of asymmetric TF-QKD.  相似文献   

16.
    
We propose a new counterfactual quantum cryptography protocol concerning about distributing a deterministic key.By adding a controlled blocking operation module to the original protocol [T.G.Noh,Phys.Rev.Lett.103(2009) 230501],the correlation between the polarizations of the two parties,Alice and Bob,is extended,therefore,one can distribute both deterministic keys and random ones using our protocol.We have also given a simple proof of the security of our protocol using the technique we ever applied to the original protocol.Most importantly,our analysis produces a bound tighter than the existing ones.  相似文献   

17.
杨璐  马鸿洋  郑超  丁晓兰  高健存  龙桂鲁 《物理学报》2017,66(23):230303-230303
量子保密通信包括量子密钥分发、量子安全直接通信和量子秘密共享等主要形式.在量子密钥分发和秘密共享中,传输的是随机数而不是信息,要再经过一次经典通信才能完成信息的传输.在量子信道直接传输信息的量子通信形式是量子安全直接通信.基于量子隐形传态的量子通信(简称量子隐形传态通信)是否属于量子安全直接通信尚需解释.构造了一个量子隐形传态通信方案,给出了具体的操作步骤.与一般的量子隐形传态不同,量子隐形传态通信所传输的量子态是计算基矢态,大大简化了贝尔基测量和单粒子操作.分析结果表明,量子隐形传态通信等价于包含了全用型量子密钥分发和经典通信的复合过程,不是量子安全直接通信,其传输受到中间介质和距离的影响,所以不比量子密钥分发更有优势.将该方案与量子密钥分发、量子安全直接通信和经典一次性便笺密码方案进行对比,通过几个通信参数的比较给出各个方案的特点,还特别讨论了各方案在空间量子通信方面的特点.  相似文献   

18.
量子密码--新一代密码技术   总被引:6,自引:0,他引:6  
本文阐述了量子密码的基本原理,着重介绍了光纤量子密码研究的最新进展。  相似文献   

19.
In this paper, we study the thermodynamic features of a two-dimensional charged black hole. Weinhold curvature and Ruppeiner curvature are explored as information geometry, respectively. Moreover, based on the Legendre invariant proposed by Hernando Quevedo, the geometro-thermodynamics behavior of this black hole is investigated.  相似文献   

20.
In general, quantum key distribution (QKD) has been proved unconditionally secure for perfect devices due to quantum uncertainty principle, quantum noneloning theorem and quantum nondividing principle which means that a quantum cannot be divided further. However, the practical optical and electrical devices used in the system are imperfect, which can be exploited by the eavesdropper to partially or totally spy the secret key between the legitimate parties. In this article, we first briefly review the recent work on quantum hacking on some experimental QKD systems with respect to imperfect devices carried out internationally, then we will present our recent hacking works in details, including passive faraday mirror attack, partially random phase attack, wavelength-selected photon-number-splitting attack, frequency shift attack, and single-photon-detector attack. Those quantum attack reminds people to improve the security existed in practical QKD systems due to imperfect devices by simply adding countermeasure or adopting a totally different protocol such as measurement-device independent protocol to avoid quantum hacking on the imperfection of measurement devices [Lo, et al., Phys. Rev. Lett., 2012, 108: 130503].  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号