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arXiv · 2504.20309

Fifth Harmonic and Five-Photon Excitation Fluorescence Multiphoton Microscopy

Joshua H. Magnus·Lam T. Nguyen·Elana G. Alevy·Travis W. Sawyer·Samuel D. Crossley·Khanh Kieu
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Abstract

We report the application of fifth order nonlinear optical processes for multiphoton microscopy, including fifth harmonic and 5-photon excitation fluorescence. This novel imaging modality has been characterized with spectral and power dependence measurements. The advantages of fifth harmonic and 5-photon excitation fluorescence imaging are higher resolution and use of longer wavelength excitation sources, which may allow deeper penetration depth, while still exciting near-UV to blue fluorophores. This imaging modality may find interesting applications in biological research, materials characterization, geologic studies, and semiconductor manufacturing.

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Joshua H. Magnus, Lam T. Nguyen, Elana G. Alevy, Travis W. Sawyer, Samuel D. Crossley, Khanh Kieu. 2025-04-28. Fifth Harmonic and Five-Photon Excitation Fluorescence Multiphoton Microscopy. https://doi.org/10.1364/ol.566910

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