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arXiv · 2008.02157

Spatial optical mode demultiplexing as a practical tool for optimal transverse distance estimation

Pauline Boucher·Claude Fabre·Guillaume Labroille·Nicolas Treps
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Abstract

We present the experimental implementation of simultaneous spatial multimode demultiplexing as a distance measurement tool. We first show a simple and intuitive derivation of the Fisher information in the presence of Poissonian noise. We then estimate the distance between two incoherent beams in both directions of the transverse plane, and find a perfect accordance with theoretical prediction, given a proper calibration of the demultiplexer. We find that, even though sensitivity is limited by the cross-talks between channels, we can perform measurements in 2 dimensions much beyond Rayleigh limit with a large dynamic.

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Pauline Boucher, Claude Fabre, Guillaume Labroille, Nicolas Treps. 2020-08-05. Spatial optical mode demultiplexing as a practical tool for optimal transverse distance estimation. https://arxiv.org/abs/2008.02157

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