Liang Yu-Jie

Quantum secure direct communication with quantum encryption based on pure entangled states

This paper presents a scheme for quantum secure direct communication with quantum encryption. The two authorized users use repeatedly a sequence of the pure entangled pairs (quantum key) shared for encrypting and decrypting the secret message carried by the travelling photons directly. For checking eavesdropping, the two parties perform the single-photon measurements on some decoy particles before each round. This scheme has the advantage that the pure entangled quantum signal source is feasible at present and any eavesdropper cannot steal the message.

Efficient Quantum Cryptography Network without Entanglement and Quantum Memory

Chun-Yan Li, Xi-Han Li, Fu-Guo Deng1,2,3†, Ping Zhou, Yu-Jie Liang, Hong-Yu Zhou 1 The Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal University, Beijing 100875 2 Institute of Low Energy Nuclear Physics, and Department of Material Science and Engineering, Beijing Normal University, Beijing 100875 3 Beijing Radiation Center, Beijing 100875 (Dated: February 1, 2008)An efficient quantum cryptography network protocol is proposed with d-dimensional polarized photons, without resorting to entanglement and quantum memory. A server on the network, say Alice, provides the service for preparing and measuring single photons whose initial state are |0. The users code the information on the single photons with some unitary operations. To prevent the untrustworthy server Alice from eavesdropping the quantum lines, a nonorthogonal-coding technique is used in the process that the quantum signal is transmitted between the users. This protocol does not require the servers and the users to store the quantum states and almost all of the single photons can be used for carrying the information, which makes it more convenient for application than others with present technology. We also discuss the case with a faint laser pulse.

Quantum Secure Direct Communication Network with Two-Step Protocol

An efficient quantum secure direct communication network protocol with the two-step scheme is proposed by using the Einstein?Podolsky?Rosen (EPR) pair block as the quantum information carrier. The server, say Alice, prepares and measures the EPR pairs in the quantum communication and the users perform the four local unitary operations to encode their message. Anyone of the legitimate users can communicate another one on the network securely. Since almost all of the instances in this scheme are useful and each EPR pair can carry two bits of information, the efficiency for qubits and the source capacity both approach the maximal values.

Multiparty Quantum Secret Report

A multiparty quantum secret report scheme is proposed with quantum encryption. The boss Alice and her M agents first share a sequence of (M+1)-particle Greenberger?Horne?Zeilinger (GHZ) states that only Alice knows which state each (M+1)-particle quantum system is in. Each agent exploits a controlled-not (CNot) gate to encrypt the travelling particle by using the particle in the GHZ state as the control qubit. The boss Alice decrypts the travelling particle with a CNot gate after performing a ?x operation on her particle in the GHZ state or not. After the GHZ states (the quantum key) are used up, the parties check whether there is a vicious eavesdropper, say Eve, monitoring the quantum line, by picking out some samples from the GHZ states shared and measuring them with two measuring bases. After confirming the security of the quantum key, they use the remaining GHZ states repeatedly for the next round of quantum communication. This scheme has the advantage of high intrinsic efficiency for the qubits and total efficiency.A multiparty quantum secret report scheme is proposed with quantum encryption. The boss Alice and her

Multiparty Quantum Remote Secret Conference

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Relativistic Mean Field Study on Halo Structures of Mirror Nuclei

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Theoretical Analysis of the Exotic Structure of 17F

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Optical Properties of Plate-Shaped ZnO Nanocrystals Grown by a Facile and Environmentally Friendly Molten Salt Method

+1)-particle Greenberger--Horne--Zeilinger (GHZ) states that only Alice knows which state each (

Theoretical Investigation of the Exotic Structure of the Mirror Nuclei 17Ne and 17N

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太陽光下でのZnOナノ粒子CuOタンポポヘテロ構造の合成とその強化された光電気化学性能【Powered by NICT】

+1)-particle quantum system is in. Each agent exploits a controlled-not (CNot) gate to encrypt the travelling particle by using the particle in the GHZ state as the control qubit. The boss Alice decrypts the travelling particle with a CNot gate after performing a