Photon-number squeezing and correlations enable measurement of absorption with an accuracy exceeding that of the shot-noise limit. However, sub-shot noise imaging and sensing based on these methods require high detection efficiency, which can be a serious obstacle if measurements are carried out in "difficult" spectral ranges. We show that this problem can be overcome through the phase-sensitive amplification before detection. Here we propose an experimental scheme of sub-shot-noise imaging with tolerance to detection losses.
@article{arxiv.1810.08115,
title = {Overcoming inefficient detection in sub-shot-noise absorption measurement and imaging},
author = {E. Knyazev and F. Ya. Khalili and M. V. Chekhova},
journal= {arXiv preprint arXiv:1810.08115},
year = {2019}
}