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arXiv · 2310.19765

Complementarity relationship between coherence and path distinguishability in an interferometer based on induced coherence

Gerard J. Machado·Lluc Sendra·Adam Vallés·Juan P. Torres
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Abstract

We consider an interferometer based on the concept of induced coherence, where two photons that originate in different second-order nonlinear crystals can interfere. We derive a complementarity relationship that links the first-order coherence between the two interfering photons with a parameter that quantifies the distinguishing information regarding the nonlinear crystal where they originated. We show that the derived relationship goes beyond the single-photon regime and is valid for any photon-flux rate generated. We report experimental results in the low photon-flux regime that confirm the validity of the derived complementarity relationship.

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Gerard J. Machado, Lluc Sendra, Adam Vallés, Juan P. Torres. 2023-10-30. Complementarity relationship between coherence and path distinguishability in an interferometer based on induced coherence. https://arxiv.org/abs/2310.19765

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