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Biphoton focusing for two-photon excitation

Magued B. Nasr·Ayman F. Abouraddy·Mark C. Booth·Michael Kempe·Ralf Wolleschensky·Bahaa E. A. Saleh·Alexander V. Sergienko·Malvin C. Teich
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Abstract

We study two-photon excitation using biphotons generated via the process of spontaneous parametric down-conversion in a nonlinear crystal. We show that the focusing of these biphotons yields an excitation distribution that is essentially the same as the distribution of one-photon excitation at the pump wavelength. We also demonstrate that biphoton excitation in the image region yields a distribution whose axial width is approximately that of the crystal thickness and whose transverse width is that of the pump at the input to the crystal.

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Magued B. Nasr, Ayman F. Abouraddy, Mark C. Booth, Michael Kempe, Ralf Wolleschensky, Bahaa E. A. Saleh, Alexander V. Sergienko, Malvin C. Teich. 2001-10-09. Biphoton focusing for two-photon excitation. https://doi.org/10.1103/physreva.65.023816

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