We propose a channel-loss-independent quantum-enhanced interferometer. In our scheme, the Fisher information for phase difference of weak light from a remote star remains constant under arbitrarily large channel loss, and the angular resolution of our method is better than that of prior quantum-enhanced methods in the long-baseline regime. Moreover, our method requires only threshold detectors and tunable coherent state or two-mode squeezed state sources, both of which are matured technologies nowadays.
@article{arxiv.2507.11342,
title = {Channel-loss-independent quantum-enhanced interferometer},
author = {Yi-Xin Shen and Zhou-Kai Cao and Jian Leng and Xiang-Bin Wang},
journal= {arXiv preprint arXiv:2507.11342},
year = {2025}
}