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Related papers: Secrecy content of two-qubit states

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A secret key shared through quantum key distribution between two cooperative players is secure against any eavesdropping attack allowed by the laws of physics. Yet, such a key can be established only when the quantum channel error rate due…

Quantum Physics · Physics 2007-05-23 H. F. Chau

Decoy states have recently been proposed as a useful method for substantially improving the performance of quantum key distribution. Here, we present a general theory of the decoy state protocol based on only two decoy states and one signal…

Quantum Physics · Physics 2009-11-11 X. Ma , B. Qi , Y. Zhao , H. -K. Lo

We look into multipartite quantum states on which quantum cryptographic protocols including quantum key distribution and quantum secret sharing can be perfectly performed, and define the quantum cryptographic resource distillable rate as…

Quantum Physics · Physics 2021-10-27 Minjin Choi , Soojoon Lee

We study cheating strategies against a practical four-state quantum bit-commitment protocol and its two-state variant when the underlying quantum channels are noisy and the cheating party is constrained to using single-qubit measurements…

Realizing secure communication between distant parties is one of quantum technology's main goals. Although quantum key distribution promises information-theoretic security for sharing a secret key, the key rate heavily depends on the level…

Quantum Physics · Physics 2025-11-05 Shin Sun , Kenneth Goodenough , Daniel Bhatti , David Elkouss

In this work, we investigate what kinds of quantum states are feasible to perform perfectly secure secret sharing, and present its necessary and sufficient conditions. We also show that the states are bipartite distillable for all bipartite…

Quantum Physics · Physics 2009-11-13 Dong Pyo Chi , Jeong Woon Choi , Jeong San Kim , Taewan Kim , Soojoon Lee

Semi-quantum key distribution protocols are designed to allow two users to establish a secure secret key when one of the two users is limited to performing certain "classical" operations. There have been several such protocols developed…

Quantum Physics · Physics 2015-09-17 Walter O. Krawec

We analyse the problem of distillation of entanglement of mixed states in higher dimensional compound systems. Employing the positive maps method [M. Horodecki et al., Phys. Lett. A 223 1 (1996)] we introduce and analyse a criterion of…

Quantum Physics · Physics 2008-02-03 Michal Horodecki , Pawel Horodecki

A quantum protocol for sharing an arbitrary two-qubit state between N parties is introduced. Any of the members, can retrieve the state, only with collaboration of the other parties. We will show that in terms of resources, i.e. the number…

Quantum Physics · Physics 2009-06-23 Razieh Annabestani , Vahid Karimipour

Quantum key distribution (QKD) protocols aim at allowing two parties to generate a secret shared key. While many QKD protocols have been proven unconditionally secure in theory, practical security analyses of experimental QKD…

Quantum Physics · Physics 2023-07-04 Michel Boyer , Gilles Brassard , Nicolas Godbout , Rotem Liss , Stéphane Virally

We present and demonstrate a new protocol for practical quantum cryptography, tailored for an implementation with weak coherent pulses to obtain a high key generation rate. The key is obtained by a simple time-of-arrival measurement on the…

Quantum Physics · Physics 2009-11-11 Damien Stucki , Nicolas Brunner , Nicolas Gisin , Valerio Scarani , Hugo Zbinden

There has been much interest in quantum key distribution. Experimentally, quantum key distribution over 150 km of commercial Telecom fibers has been successfully performed. The crucial issue in quantum key distribution is its security.…

Quantum Physics · Physics 2009-11-10 Hoi-Kwong Lo , Xiongfeng Ma , Kai Chen

In this paper, a semiquantum secret sharing (SQSS) protocol based on x-type states is proposed, which can accomplish the goal that only when two classical communicants cooperate together can they extract the shared secret key of a quantum…

Quantum Physics · Physics 2022-12-13 Ying Chen , Tian-Yu Ye

We propose a scheme for quantum key distribution (QKD) protocol with dual-rail displaced photon states. Displaced single photon states carry bit value of code which may be extracted while coherent states carry nothing and they only provide…

Quantum Physics · Physics 2015-05-13 Sergey A. Podoshvedov

We report experimental generation of a noisy entangled four-photon state that exhibits a separation between the secure key contents and distillable entanglement, a hallmark feature of the recently established quantum theory of private…

Quantum key agreement requires all participants to recover the shared key together, so it is crucial to resist the participant attack. In this paper, we propose a verifiable multi-party quantum key agreement protocol based on the six-qubit…

Quantum Physics · Physics 2021-07-21 Li-Juan Liu , Zhi-Hui Li

We present a new technique for proving the security of quantum key distribution (QKD) protocols. It is based on direct information-theoretic arguments and thus also applies if no equivalent entanglement purification scheme can be found.…

Quantum Physics · Physics 2009-11-11 R. Renner , N. Gisin , B. Kraus

A quantum key distribution protocol based on entanglement swapping is proposed. Through choosing particles by twos from the sequence and performing Bell measurements, two communicators can detect eavesdropping and obtain the secure key.…

Quantum Physics · Physics 2007-05-23 Fei Gao , Fenzhuo Guo , Qiaoyan Wen , Fuchen Zhu

The heralded exact one-way distillable secret key is equal to the largest expected rate at which perfect secret key bits can be probabilistically distilled from a bipartite state by means of local operations and one-way classical…

Quantum Physics · Physics 2026-03-11 Vishal Singh , Mark M. Wilde

Magic states, by allowing non-Clifford gates through gate teleportation, are important building blocks of fault-tolerant quantum computation. Magic state distillation protocols aim to create clean copies of magic states from many noisier…

Quantum Physics · Physics 2026-03-05 Heather Leitch , Yingkai Ouyang