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arXiv · 2004.07228

Superresolution Limits from Measurement Crosstalk

Manuel Gessner·Claude Fabre·Nicolas Treps
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Abstract

Superresolution techniques based on intensity measurements after a spatial mode decomposition can overcome the precision of diffraction-limited direct imaging. However, realistic measurement devices always introduce finite crosstalk in any such mode decomposition. Here, we show that any nonzero crosstalk leads to a breakdown of superresolution when the number $N$ of detected photons is large. Combining statistical and analytical tools, we obtain the scaling of the precision limits for weak, generic crosstalk from a device-independent model as a function of the crosstalk probability and $N$. The scaling of the smallest distance that can be distinguished from noise changes from $N^{-1/2}$ for an ideal measurement to $N^{-1/4}$ in the presence of crosstalk.

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Manuel Gessner, Claude Fabre, Nicolas Treps. 2020-04-15. Superresolution Limits from Measurement Crosstalk. https://doi.org/10.1103/physrevlett.125.100501

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