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arXiv · 1901.02688

Interferometric Autocorrelation Measurements of Supercontinuum based on Two-Photon Absorption

Shanti Toenger·Roosa Mäkitalo·Jani Ahvenjärvi·Piotr Ryczkowski·Mikko Närhi·John M. Dudley·Goëry Genty
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Abstract

We report on interferometric autocorrelation measurements of broadband supercontinuum light in the anomalous dispersion regime using two-photon absorption in a GaP photodetector. The method is simple, low-cost, and provides a direct measure of the second-order coherence properties, including quantitative information on the coherence time and average duration of the supercontinuum pulses as well as on the presence of temporally coherent sub-structures. We report measurements in regimes where the supercontinuum is coherent and incoherent. In the former case, the interferometric measurements are similar to what is observed for mode-locked laser pulses while in the latter case the interferometric measurements and coherence properties are shown to have characteristics similar to that of a stationary chaotic light source.

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Shanti Toenger, Roosa Mäkitalo, Jani Ahvenjärvi, Piotr Ryczkowski, Mikko Närhi, John M. Dudley, Goëry Genty. 2019-01-09. Interferometric Autocorrelation Measurements of Supercontinuum based on Two-Photon Absorption. https://doi.org/10.1364/josab.36.001320

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