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arXiv · 2003.03635

Measurement of coupled spatiotemporal coherence of parametric down-conversion under negative group velocity dispersion

Paula Cutipa·Kirill Yu. Spasibko·Maria V. Chekhova
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Abstract

We present a direct measurement of the spatiotemporal coherence of parametric down-conversion in the range of negative group-velocity dispersion. In this case, the frequency-angular spectra are ring-shaped and temporal coherence is coupled to spatial coherence. Correspondingly, the lack of coherence due to spatial displacement can be compensated with the introduction of time delay. We show a simple technique, based on a modified Mach-Zehnder interferometer, which allowed us to measure time coherence and near-field space coherence simultaneously, with complete control of both variables. This technique will be also suitable for the measurement of second-order coherence, where the main applications are related to the two-photon spectroscopy.

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Paula Cutipa, Kirill Yu. Spasibko, Maria V. Chekhova. 2020-03-07. Measurement of coupled spatiotemporal coherence of parametric down-conversion under negative group velocity dispersion. https://doi.org/10.1364/ol.397700

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