Unbalanced-basis-misalignment-tolerant measurement-device-independent quantum key distribution

Abstract

Measurement-device-independent quantum key distribution (MDIQKD) is a revolutionary protocol since it is physically immune to all attacks on the detection side. However, the protocol still keeps the strict assumptions on the source side that specify that the four BB84 states must be perfectly prepared to ensure security. Some protocols release part of the assumptions in the encoding system to keep the practical security, but the performance would be dramatically reduced. In this work, we present a MDIQKD protocol that requires less knowledge of the encoding system to combat the troublesome modulation errors and fluctuations. We have also experimentally demonstrated the protocol. The result indicates a high performance and good security for practical applications. Its robustness and flexibility also exhibit a good value for complex scenarios such as the QKD networks.