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arXiv · 2212.13873

Mode structure reconstruction by detected and undetected light

Laura T. Knoll·Giulia Petrini·Fabrizio Piacentini·Paolo Traina·Sergey V. Polyakov·Ekaterina Moreva·Ivo Pietro Degiovanni·Marco Genovese
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Abstract

We introduce a novel technique for the reconstruction of multimode optical fields, based on simultaneously exploiting both the generalized Glauber's $K^{th}$-order correlation function $g^{(K)}$ and a recently proposed anti-correlation function (dubbed $\theta^{(K)}$) which is resilient to Poissonian noise. We experimentally demonstrate that this method yields mode reconstructions with higher fidelity with respect to those obtained with reconstruction methods based only on $g^{(K)}$'s, even requiring less "a priori" information. The reliability and versatility of our technique make it suitable for a widespread use in real applications of optical quantum measurement, from quantum information to quantum metrology, especially when one needs to characterize ensembles of single-photon emitters in the presence of background noise (due, for example, to residual excitation laser, stray light, or unwanted fluorescence).

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Laura T. Knoll, Giulia Petrini, Fabrizio Piacentini, Paolo Traina, Sergey V. Polyakov, Ekaterina Moreva, Ivo Pietro Degiovanni, Marco Genovese. 2022-12-28. Mode structure reconstruction by detected and undetected light. https://doi.org/10.1002/qute.202300062

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