摘要
Long-distance entanglement distribution is fundamental to the establishment of a large-scale quantum network,particularly in systems that operate without the need for trusted relays.Here,we demonstrate entanglement-based quantum key distribution over 343 km of fiber spools using multi-wavelength single-photon-level calibration light for reference frame alignment.By co-propagating calibration and entangled photons through identical paths and sharing detectors in a time-multiplexed manner,a polarization purity of 2783 achieves for two mutually unbiased bases.The system operates continuously for 27.1 h in the laboratory,generating a total of 253 bits secure key at an asymptotic secure key rate of 3.68×10^(−3)bps.This work provides a viable approach for constructing large-scale quantum network.
基金
supported by the National Natural Science Foundation of China(Grant No.62171458)
the Shenzhen Science and Technology Program(Grant No.JCYJ20220818102014029)
the Science and Technology Innovation Program of Hunan Province(Grant No.2023RC3003).
