A Simultaneous Quantum Secure Direct Communication Scheme between the Central Party and Other M Parties

Song‐Kong Chong, Tzonelih Hwang

Lianying Wang, Xiu‐Bo Chen, Gang Xu +1 more

Gao Ting, Yan Feng-Li, Wang Zhi-Xi +1 more

We analyse the capacity of a simultaneous quantum secure direct communication scheme between the central party and other M parties via M +1-particle GHZ states and swapping quantum entanglement. It is shown that the encoding scheme should be secret if other M parties wants to transmit M +1 bit classical messages to the centre party secretly. However, when the encoding scheme is announced publicly, we prove that the capacity of the scheme in transmitting the secret messages is 2 bits, no matter how large M is.

Lu Yin-Ju

Gao Ting, Yan Feng-Li, Zhi‐Xi Wang

We propose a simultaneous quantum secure direct communication scheme between one party and other three parties via four-particle GHZ states and swapping quantum entanglement. In the scheme, three spatially separated senders, Alice, Bob and Charlie, transmit their secret messages to a remote receiver Diana by performing a series of local operations on their respective particles according to the quadripartite stipulation. From Alice, Bob, Charlie and Diana's Bell measurement results, Diana can infer the secret messages. If a perfect quantum channel is used, the secret messages are faithfully transmitted from Alice, Bob and Charlie to Diana via initially shared pairs of four-particle GHZ states without revealing any information to a potential eavesdropper. As there is no transmission of the qubits carrying the secret message in the public channel, it is completely secure for the direct secret communication. This scheme can be considered as a network of communication parties where each party wants to communicate secretly with a central party or server.

刘丹, 裴昌幸, 权东晓 +1 more