Source temporal imperfections in measurement-device-independent quantum key distribution
Phys. Rev. A 114, 042435 – Published 16 October, 2026
DOI: https://doi.org/10.1103/w55c-w4pg
Abstract
In high-speed quantum key distribution systems, the repetition rate is a critical factor limiting system efficiency. In the implementation of the measurement-device-independent quantum key distribution protocol based on two-photon interference, inherent temporal imperfections can significantly impact the system's repetition rate. We establish a systematic scheme for three temporal imperfections: time jitter, pulse shape imperfection, and interpulse interference. By discretizing time into time units and calculating the interference within each, we quantitatively characterize how temporal misalignment affects two-photon interference. Using this scheme, we simulate a specific experimental system based on the four-intensity protocol, and through parameter optimization, achieve a higher key rate. The approach thus offers a concrete pathway for enhancing the efficiency in the experimental realization of high-performance systems.
