Experimental demonstration of reference-frame-independent measurement-device-independent quantum key distribution over asymmetric channels
Phys. Rev. A 113, 063715 – Published 11 June, 2026
DOI: https://doi.org/10.1103/hvhq-768x
Abstract
Reference-frame-independent measurement-device-independent quantum key distribution (RFI-MDI-QKD) offers a promising approach for building star-type quantum secure networks, removing the need for reference frame alignment and eliminating all detector side channel attacks. While prior experiments confirmed the practicality of RFI-MDI-QKD, they largely assume symmetric channels, an idealization rarely met in real networks. Here, we present an experimental demonstration of RFI-MDI-QKD under asymmetric channel loss. By combining an optimized seven-intensity decoy-state method with a joint-study method, we achieve a secret key rate of 46.47 bit/s over 100 km with an asymmetric channel (Alice at 40 km and Bob at 60 km), surpassing the key rate of conventional added-attenuation methods by more than tenfold. These results pave the way for high-rate, ultrasecure quantum networks.
