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arXiv · 2608.07868

Sub-Rayleigh Imaging of Unequal-Intensity Sources: Near-Quantum-Limit Multiparameter Estimation

Y. Batuhan Yilmaz·Kent A. G. Bonsma-Fisher·Muhammad Mohid·Noah Lupu-Gladstein·Arthur O. T. Pang·Aephraim M. Steinberg
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Abstract

In optical imaging, diffraction strongly degrades the performance of conventional intensity-based estimation once the separation between two sources is below the Rayleigh-Abbe limit. Recent developments showed that this limitation can be surpassed using spatial-mode demultiplexing (SPADE), and this was demonstrated in several experiments for two equal-intensity spots of unknown separation. When there are multiple unknown parameters, as in the case of several unequal sources with unknown intensities and unknown separation, cross-talk among the parameters makes the multi-parameter estimation problem significantly more challenging. In this paper, we adapt super-resolved position localization by inversion of coherence along an edge (SPLICE) to estimate both the separation and relative intensity of two incoherent sources simultaneously. We demonstrate a clear advantage over direct imaging (DI), achieving a root mean squared error (RMSE) approximately $50 \%$ larger than the quantum limit and a sixfold improvement over DI within the range of parameters we tested. This improvement can be even greater for smaller separations and larger intensity imbalances when crosstalk is suppressed.

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Y. Batuhan Yilmaz, Kent A. G. Bonsma-Fisher, Muhammad Mohid, Noah Lupu-Gladstein, Arthur O. T. Pang, Aephraim M. Steinberg. 2026-08-08. Sub-Rayleigh Imaging of Unequal-Intensity Sources: Near-Quantum-Limit Multiparameter Estimation. https://arxiv.org/abs/2608.07868

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