In a recent work, Markham and Sanders have proposed a framework to study quantum secret sharing (QSS) schemes using graph states. This framework unified three classes of QSS protocols, namely, sharing classical secrets over private and public channels, and sharing quantum secrets. However, most work on secret sharing based on graph states focused on threshold schemes. In this paper, we focus on general access structures. We show how to realize a large class of arbitrary access structures using the graph state formalism. We show an equivalence between $[[n,1]]$ binary quantum codes and graph state secret sharing schemes sharing one bit. We also establish a similar (but restricted) equivalence between a class of $[[n,1]]$ Calderbank-Shor-Steane (CSS) codes and graph state QSS schemes sharing one qubit. With these results we are able to construct a large class of quantum secret sharing schemes with arbitrary access structures.
Quantum secret sharing allows each player to have classical information for secret sharing in quantum mechanical ways. In this work, we construct a class of quantum states on which players can quantumly perform secret sharing secure against dishonest players as well as eavesdropper. We here call them the genuine secret-sharing states. In addition, we show that if $N$ players share an $N$-party genuine secret-sharing state, then arbitrary $M$ players out of the total players can share an $M$-party genuine secret-sharing state by means of local operations and classical communication on the state…
Eavesdropping on the improved three-party quantum secret sharing protocol
Lin等[S. Lin，F. Gao，Q.- y. Wen，F.- C. Zhu，Opt. Commun. 281（2008）4553]指出多方量子秘密共享协议[Z.- j. Zhang，G. Gao、X.王湖，澳-地F.汉，S.- H. Shi，Opt. Commun. 269（2007）418]是不安全的，提出了一种改进的三方量子秘密共享协议。本文研究了改进的三方量子秘密共享协议的安全性，发现它仍然是不安全的。最后，提出了一个进一步改进的三方量子秘密共享协议。
Quantum secret sharing is well known as a method for players to share a classical secret for secret sharing in quantum mechanical ways. Most of the results associated with quantum secret sharing are based on pure multipartite entangled states. In reality, however, it is difficult for players to share a pure entangled state, although they can share a state close to the state. Thus, it is necessary to study how to perform the quantum secret sharing based on a general multipartite state. We here present a quantum secret sharing protocol on an $N$-qubit state close to a pure $N$-qubit Greenberger-…
This comment points out a problem in Song et al.'s (t, n) threshold quantum secret sharing [Scientific Reports, Vol. 7, No. 1 (2017), pp. 6366], indicating that the agent is unable to obtain the expected information.
We propose here a quantum secret sharing scheme that works for both quantum and classical secrets. The proposed scheme is based on both entanglement swapping and teleportation together. It allows sender to encrypt his/her secret and simultaneously distribute decryption information of the encrypted secret among distant parties where decryption shares are nonlocally correlated with each other. Two-fold quantum non-local correlations, generated through entanglement swapping and then teleporting quantum states over swapped maximally entangled pairs, guarantee both authentication and secrecy of the…
Quantum secret sharing is a scheme for encoding a quantum state (the secret) into multiple shares and distributing them among several participants. If a sufficient number of shares are put together, then the secret can be fully reconstructed. If an insufficient number of shares are put together however, no information about the secret can be revealed. In quantum ramp secret sharing, partial information about the secret is allowed to leak to a set of participants, called an unqualified set, that cannot fully reconstruct the secret. By allowing this, the size of a share can be drastically reduce…
本文将Hillary，Bužek和Berthiaume[Phys. Rev. A59，1829（1999）]的量子秘密共享方案推广到任意多方。给出了共享秘密位的显式表达式。结果表明，在Hillery-Bužek-Berthiaume量子秘密共享方案中，秘密信息是以参与者的测量结果所形成的二进制串的奇偶性来共享的.此外，我们还推广了量子密钥分发中的两种技术，从而提高了量子秘密共享方案的效率。最优测量基量子秘密共享方案是在Lo-Chau-Ardehali技术的基础上发展起来的[H. K. Lo，H. F. Chau和M. Ardehali，quant-ph/0011056]，其中所有参与者非对称地选择测量基，测量基加密的量子秘密共享方案是在Hwang-Koh-Han技术[W. Y.黄岛G. Koh和Y. D. Han，Phys. Lett. A244，489（1998）]，其中所有参与者根据控制键选择他们的测量基础。这两个方案的效率都是渐近的100%，因此几乎所有的量子秘密共享过程中的GHZ态被用来产生共享的秘密信息。
In the paper [Quantum Inf. Process. 14, 4237-4244 (2015)], Qin and Dai proposed a proactive quantum secret sharing scheme. We study the security of the proposed scheme and find that it is not secure. In the distribution phase of the proposed scheme, two dishonest participants may collaborate to eavesdrop the secret of the dealer without introducing any error. Incidentally, a possible improvement of the distribution phase is given.
With the advantages of both classical and quantum secret sharing, many practical hybrid quantum secret sharing have been proposed. In this paper, we propose a hybrid quantum secret sharing scheme based on mutually unbiased bases and monotone span program. First, the dealer sends the shares in the linear secret sharing to the participants in the authorization set via a secure channel. Then, the dealer and participants perform unitary transformation on a d-dimensional quantum state sequentially, and the dealer publishes the measurement result confidentially to the participants in the authorizati…
In this work we address the issue of sharing a quantum secret over untrusted channels between the dealer and players. Existing methods require entanglement over a number of systems which scales with the security parameter, quickly becoming impractical. We present protocols (interactive and a non-interactive) where single copy encodings are sufficient. Our protocols work for all quantum secret sharing schemes and access structures, and are implementable with current experimental set ups. For a single authorised player, our protocols act as quantum authentication protocols.
A ($t$, $n$) threshold quantum secret sharing (QSS) is proposed based on a single $d$-level quantum system. It enables the ($t$, $n$) threshold structure based on Shamir's secret sharing and simply requires sequential communication in $d$-level quantum system to recover secret. Besides, the scheme provides a verification mechanism which employs an additional qudit to detect cheats and eavesdropping during secret reconstruction, and allows a participant to use the share repeatedly. Analyses show that the proposed scheme is resistant to typical attacks. Moreover, the scheme is salable in partici…
An information theoretical model for quantum secret sharing was introduced by A. C. A. Nascimento et al.[Quantum Inf. Comput. Vol.5,1,205,68-79(2003)], which was analyzed by quantum information theory. In this paper, we analyze this information theoretical model using the properties of the quantum access structure. By the analysis we propose a generalized model definition for the quantum secret sharing schemes. In our model, there are more quantum access structures which can be realized by our generalized quantum secret sharing schemes than those of the previous one. In addition, we also analy…
Our aim is to formulate continuous-variable quantum secret sharing as a continuous-variable ramp quantum secret sharing protocol, provide a certification procedure for it and explain the criteria for the certification. Here we introduce a technique for certifying continuous-variable ramp quantum secret-sharing schemes in the framework of quantum interactive-proof systems. We devise pseudocodes in order to represent the sequence of steps taken to solve the certification problem. Furthermore, we derive the expression for quantum mutual information between the quantum secret extracted by any mult…
Quantum secret sharing with continuous-variable cluster states
我们扩展了簇态量子秘密共享的形式主义，如Markham和Sanders [Phys.Rev.A78，042309（2008）]和Keet等人[Phy. Rev. A 82，062315（2010）]，到连续变量方案。我们表明，经典和量子信息可以通过分配连续变量集群状态通过公共或私人渠道共享。我们发现，如果集团态是无限压缩的，对手的结构是完全否认从秘密，但如果采用一个现实的双压缩状态将泄露一些秘密信息。我们建议的基准来评估的安全性，在挤压的情况下。对于经典秘密的共享，我们借用了连续变量量子密钥分发的技术来计算秘密共享率。对于量子态的共享，我们估计了从每个团簇态中提取的用于隐形传态的纠缠量。
Secure Quantum Secret Sharing Based on Reusable GHZ States as Secure Carriers
我们证明了当合法用户使用安全载体在协议中重复地对经典信息进行编码和解码时，潜在的窃听者可以窃听整个秘密信息[Bagherinezhad S和Karimipour V 2003 Phys. Rev. A \textbf{67} 044302中提出]。在此基础上，我们提出了一个改进的量子秘密共享协议，该协议以Greenberger-Horne-Zeilinger态为安全载体。我们的协议可以抵抗夏娃的攻击
Single qubit quantum secret sharing with improved security
仔细分析了一个实验上可行的非纠缠单量子比特量子秘密共享协议及其改进版本[Phys. Rev. Lett. 95，230505（2005）;同上，98，028902（2007）]，发现这两个版本对于相干攻击都是不安全的，尽管最初的想法是如此显著。为了克服这个致命的缺陷，在这里，我们提出了一个协议与一个独特的安全检查策略，它仍然只涉及单量子比特操作，使它有可能实现更好的安全性与现有技术的量子秘密共享。
A corresponding comment, raised by Kao and Hwang, claims that the reconstructor Bob1 is unable to obtain the expected secret information in (t, n) Threshold d-level Quantum Secret Sharing (TDQSS)[Scientific Reports, Vol. 7, No. 1 (2017), pp.6366] . In this reply, we show the TDQSS scheme can obtain the dealer's secret information in the condition of adding a step on disentanglement.
Secret sharing, in which a dealer wants to split a secret in such a way that any unauthorized subset of parties is unable to reconstruct it, plays a key role in cryptography. The security of quantum protocols for the task is guaranteed by the fact that Eve's any strategies to obtain secret information from encoded quantum states should cause a disturbance in the signal. Here, we propose a quantum secret sharing (classical information) scheme for $N$ parties based on totally different principle in which monitoring signal disturbance is no longer need. In this scheme, the secret is divided among…
In this paper [Chin. Phys. B 27 (2018) 080304], Du and Bao proposed a quantum secret sharing protocol based on two-particle transform of Bell states. We study the security of the proposed protocol and find that it is not secure, that is, the two dishonest agents, Bob and Zach, can collude to obtain Alice's secret messages without the help of the other agents. Finally, we give a possible improvement of the proposed protocol.
Quantum secret sharing is a way to share secret messages among the clients in a group with complete security. For the first time, Hillery et al. (Phys Rev A 59:1829, 1999) proposed the quantum version of the classical secret sharing protocol using GHZ states. Here, we implement the above quantum secret sharing protocol in 'IBM Q 5 Tenerife' quantum processor and compare the experimentally obtained results with the theoretically predicted ones. Further, a new quantum binary voting protocol is proposed and implemented in the 14-qubit 'IBM Q 14 Melbourne' quantum processor. The results are analyz…
