中文摘要：

Measurement-device-independent 量钥匙分发(MDI-QKD ) 对察觉者方面隧道攻击有免疫力，它是在传统的 QKD 的一个关键安全枪眼问题。以便放松来源在 MDI-QKD 被信任的一个关键假设，与 untrusted 来源一起的一个 MDI-QKD 协议被建议了。为与 untrusted 来源一起的 MDI-QKD 的安全，在实际实验的瑕疵应该也被考虑。在这份报纸，我们与 untrusted 来源一起在一个圈套状态 MDI-QKD 协议的安全上分析内部发射度的变化的效果。我们的数字结果两个都显示出那当考虑内部发射度的变化时，秘密的关键率和最大的安全传播距离减少。特别，当抽筋吝啬的光子数字每脉搏是更小的时，他们是更敏感的。我们的结果强调关联词的稳定性光设备为实际实现是重要的。

英文摘要：

Measurement-device-independent quantum key distribution （MDI-QKD） is immune to detector side channel attacks, which is a crucial security loophole problem in traditional QKD. In order to relax a key assumption that the sources are trusted in MDI-QKD, an MDI-QKD protocol with an untrusted source has been proposed. For the security of MDI-QKD with an untrusted source, imperfections in the practical experiment should also be taken into account. In this paper, we analyze the effects of fluctuations of internal transmittance on the security of a decoy-state MDI-QKD protocol with an untrusted source. Our numerical results show that both the secret key rate and the maximum secure transmission distance decrease when taken fluctuations of internal transmittance into consideration. Especially, they are more sensitive when Charlie＇s mean photon number per pulse is smaller. Our results emphasize that the stability of correlative optical devices is important for practical implementations.