Continuous-variable quantum key distribution with Gaussian source noise

Yujie Shen, Xiang Peng, Jian Yang, Hong Guo

Published 2011-01-05, updated 2011-05-09Version 2

Source noise affects the security of continuous-variable quantum key distribution (CV QKD), and is diffcult to analyze. We propose a model to characterize Gaussian source noise through introducing a neutral party (Fred) who induces the noise with a general unitary transformation. Without knowing Fred's exact state, we derive the security bounds for both reverse and direct reconciliations and show that the bound for reverse reconciliation is tight.