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arXiv · 2208.11387

Witnessing Entangled Two-Photon Absorption via Quantum Interferometry

Áulide Martínez-Tapia·Samuel Corona-Aquino·Chenglong You·Rui-Bo Jin·Omar S. Magaña-Loaiza·Shi-Hai Dong·Alfred B. U'Ren·Roberto de J. León-Montiel
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Abstract

Recent investigations suggest that the use of non-classical states of light, such as entangled photon pairs, may open new and exciting avenues in experimental two-photon absorption spectroscopy. Despite several experimental studies of entangled two-photon absorption (eTPA), there is still a heated debate on whether eTPA has truly been observed. This interesting debate has arisen, mainly because it has been recently argued that single-photon-loss mechanisms, such as scattering or hot-band absorption may mimic the expected entangled-photon linear absorption behavior. In this work, we focus on transmission measurements of eTPA, and explore three different two-photon quantum interferometers in the context of assessing eTPA. We demonstrate that the so-called N00N-state configuration is the only one amongst those considered insensitive to linear (single-photon) losses. Remarkably, our results show that N00N states may become a potentially powerful tool for quantum spectroscopy, and place them as a strong candidate for the certification of eTPA in an arbitrary sample.

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Áulide Martínez-Tapia, Samuel Corona-Aquino, Chenglong You, Rui-Bo Jin, Omar S. Magaña-Loaiza, Shi-Hai Dong, Alfred B. U'Ren, Roberto de J. León-Montiel. 2022-08-24. Witnessing Entangled Two-Photon Absorption via Quantum Interferometry. https://arxiv.org/abs/2208.11387

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