Implementation of an M-ary Three-Stage Quantum Cryptography Protocol

摘要

This paper introduces an m-ary version of the Three-stage Quantum Cryptography protocol. The three-stage protocol was first proposed in 2006 and implemented in 2012. The m-ary version of the three-stage protocol proposed in this paper results in enhanced data transfer between a sender Alice and a receiver Bob since each pulse carries more than one bit of information. An experimental realization of the m-ary three-stage protocol is also reported in this paper. The implementation has used free-space optics as the transmission medium and passive optical components controlled through Lab View. Furthermore, analytical results that address the impact of the noise factor and its trade-off with data rate are presented. This analysis includes a study of the probability of errors and channel capacity variations in terms of the noise variance factor for the m-ary three-stage protocol using two, four and eight levels. Limits within which the m-ary three-stage protocol can be used with higher performance efficiency compared to its original version counterpart are set.