A new quantum dialogue (QD) protocol with single photons is proposed. In the proposed protocol, two participants perform different operations according to their own secret information. A key previously shared by the two communicants through a secure QKD protocol is used to control not only the encoding operation of the dialogue initiator but also security detection. The analysis on efficiency demonstrates the proposed protocol is more efficient.
A new quantum dialogue (QD) protocol with single photons is proposed. In the proposed protocol, two participants perform different operations according to their own secret information. A key previously shared by the two communicants through a secure QKD protocol is used to control not only the encoding operation of the dialogue initiator but also security detection. The analysis on efficiency demonstrates the proposed protocol is more efficient.
A quantum dialogue protocol is proposed and proved to be secure. In our scheme, single photons are used as a quantum channel, the security of our scheme is guaranteed by BB84 QKD and the fact that controlled-not operation ensures the control qubit is unchanged and the target qubit flips only if the control qubit is . By using controlled-not operations, two legitimate communicators can share a private initial state and realize quantum dialogue securely. Compared with previous quantum dialogue protocols, the good merit of this work is that the insecurity, i.e. ‘information leakage’ is eliminated. Comparing this dialogue protocol with the recent work in another paper [Shi, G.F.; Xi, X.Q.; Hu, M.L.; Yue, R.H. Opt. Commun. 2010, 283, 1984] where two adjacent single photons must be of the same quantum state, this scheme is experimentally simple.
Abstract Quantum dialogue (QD) is a term of quantum cryptography, which can fulfill the secure exchange of two parties’ private information in an open environment. Up to now, there have been a lot of QD protocols. Many have several common components and activities, such as encoding photons coming forth with auxiliary photons and back, one party or both performing unitary operations on encoding photons, two times of security check, and both parties’ private data being decoded chronologically from encoding photons. This work proposes a brand-new QD model, whose quantum transmission is unidirectional with only one security check and decoding of both parties’ secrets are simultaneous. Equally important is neither unitary operations nor auxiliary photons being used. Consequently, such a QD can substantially reduce costs and increase efficiency, thus entitled fast quantum dialogue (FQD). The presented FQD protocol is analysed with safety and without information leakage. Moreover, its information-theoretical efficiency is 88.89%, much higher than the current maximum 66.67%. So, it offers us a better alternative for QD.
In this paper, a quantum dialogue (QD) protocol without information leakage is proposed at first by using single photons as the quantum resource, where each single photon is directly encoded for transmitting secret messages. Two communication parties share the quantum state generation rule in advance. The preparation party reads out the other party's secret messages by virtue of quantum secure direct communication. The other party decodes out the preparation party's secret messages with the aid of a classical information sequence indicating the preparation bases of single photons sent from the preparation party. In this way, the information leakage problem is avoided. The proposed protocol with single photons only needs the single-photon measurements. Different from Shi's two recent QD protocols based on single photons, the proposed protocol with single photons needs neither to prepare two adjacent single photons in the same quantum state nor to perform the controlled-not (CNOT) operations. Finally, the proposed protocol with single photons is generalized into the cases of resisting collective-dephasing noise and collective-rotation noise by using logical qubits as the quantum resource, respectively.
In this paper, a novel information-leakage-resistant quantum dialogue (QD) protocol with single photons in both polarization and spatial-mode degrees of freedom is proposed. This protocol utilizes quantum encryption technology to overcome the information leakage problem; the protocol utilizes quantum encryption and decoy photon technologies to dually protect the single photons with two degrees of freedom used for encoding two communicants’ private classical bits, and makes the initial states of the single photons with two degrees of freedom for encoding shared between two communicants through quantum key encryption and decryption. The information-theoretical efficiency of this protocol is 40%.
An efficient practical feasible protocol for quantum secure dialogue by using single photons is proposed. Comparing with the previous protocols, in the proposed protocol, no classical message has to exchanged during the decoding of the secret messages, so the present scheme is not only overcome the drawback “information leakage”, it possesses the characters of security and maximum efficiency. The other highlight of our protocol is that, in this method one party is able to first read the message received from the other party before sending another message back in reply.
Semi-quantum dialogue (SQD) enables secure bidirectional communication even when one participant has limited quantum capabilities. In order to solve the problems of low efficiency and quantum resource constraints, an efficient SQD protocol using single-photon is proposed. In the SQD, one communicating party needs to have semi-quantum capabilities to complete the dialogue, which could consume lower quantum resource. Moreover, single photons as quantum channels significantly reduces both preparation and operational costs. Finally, decryption can be performed without any classical disclosure, effectively preventing potential information leakage. Security analysis demonstrates resilience against common attacks, including intercept-resend, measure-resend, entanglement-measurement, and Trojan horse attacks, with no information leakage. Compared with existing semi-quantum dialogue protocols, our proposed protocol consumes fewer quantum resources while achieving higher communication efficiency and enhanced security.