Deterministic secure quantum communication with practical devices

Abstract

Deterministic secure quantum communication (DSQC) can transmit ciphered message with information theoretical security, in which the message is directly modulated on the quantum state and transmitted from Alice to Bob. Thus, key is not pre-shared, but rather communicated after the security of the ciphered message transmission is assured. In most of previous DSQC protocols, quantum memory or entanglement is necessary, which is still a big challenge with current technology. And the imperfections of practical devices, such as loss, weak coherent source, and so on, may also down play the security and efficiency of these DSQC protocols. In this article, a DSQC protocol with practical devices is proposed. In our protocol, both quantum memory and entanglement are not require. And DSQC with distance as long as 100–200 km and repetition as high as is possible.