Quantum Secure Direct Communication Network with Two-Step Protocol
LI Xi-Han1,2, ZHOU Ping1,2, LIANG Yu-Jie1,2, LI Chun-Yan1,2, ZHOU Hong-Yu1,2,3, DENG Fu-Guo1,2,3
1The Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal University, Beijing 100875
2Institute of Low Energy Nuclear Physics, and Department of Material Science and Engineering, Beijing Normal University, Beijing 100875
3Beijing Radiation Center, Beijing 100875
Quantum Secure Direct Communication Network with Two-Step Protocol
LI Xi-Han1,2;ZHOU Ping1,2;LIANG Yu-Jie1,2;LI Chun-Yan1,2;ZHOU Hong-Yu1,2,3;DENG Fu-Guo1,2,3
1The Key Laboratory of Beam Technology and Material Modification of Ministry of Education, Beijing Normal University, Beijing 100875
2Institute of Low Energy Nuclear Physics, and Department of Material Science and Engineering, Beijing Normal University, Beijing 100875
3Beijing Radiation Center, Beijing 100875
Abstract： 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.
LI Xi-Han;ZHOU Ping;LIANG Yu-Jie;LI Chun-Yan;ZHOU Hong-Yu;;DENG Fu-Guo;. Quantum Secure Direct Communication Network with Two-Step Protocol[J]. 中国物理快报, 2006, 23(5): 1080-1083.
LI Xi-Han, ZHOU Ping, LIANG Yu-Jie, LI Chun-Yan, ZHOU Hong-Yu, , DENG Fu-Guo,. Quantum Secure Direct Communication Network with Two-Step Protocol. Chin. Phys. Lett., 2006, 23(5): 1080-1083.
2006, Vol. 23 
