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arXiv · 2008.02664

Setting bounds on two-photon absorption cross-sections in common fluorophores with entangled photon pair excitation

Kristen M. Parzuchowski·Alexander Mikhaylov·Michael D. Mazurek·Ryan N. Wilson·Daniel J. Lum·Thomas Gerrits·Charles H. Camp Jr.·Martin J. Stevens·Ralph Jimenez
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Abstract

Excitation with entangled photon pairs may lead to an increase in the efficiency of two-photon absorption at low photon flux. The corresponding process, entangled two-photon absorption (E2PA), has been investigated in numerous theoretical and experimental studies. However, significant ambiguity and inconsistency remain in the literature about the absolute values of E2PA cross-sections. Here, we use a fluorescence-based registration scheme to experimentally determine upper bounds on the cross-sections for six fluorophores. These bounds are up to four orders of magnitude lower than the smallest published cross-section. For two samples that have been studied by others, Rhodamine 6G and 9R-S, we measure upper bounds four and five orders of magnitude lower than the previously reported cross-sections.

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Kristen M. Parzuchowski, Alexander Mikhaylov, Michael D. Mazurek, Ryan N. Wilson, Daniel J. Lum, Thomas Gerrits, Charles H. Camp Jr., Martin J. Stevens, Ralph Jimenez. 2020-08-06. Setting bounds on two-photon absorption cross-sections in common fluorophores with entangled photon pair excitation. https://doi.org/10.1103/physrevapplied.15.044012

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