Performance analysis of polarization coding BB84 quantum key distribution system under non-Markovian channel

The characteristics of quantum channel play important roles on designing a high performance quantum communication system. In this paper, we analyze the fidelity of polarization state travelling through a non-Markovian optical fiber depolarizing quantum channel with color noise environment. The quantum bit error rate (QBER) of a polarization coding BB84 quantum key distribution (QKD) system under non-Markovian depolarizing channel is also discussed. Analysis results show that there are several security regions caused by the fluctuation of QBER in such a non-Markovian channel. These will provide references for designing polarization compensation scheme and estimating of secure distance.