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Joint spectrum of photon pairs measured by coincidence Fourier spectroscopy

Wojciech Wasilewski·Piotr Wasylczyk·Piotr Kolenderski·Konrad Banaszek·Czeslaw Radzewicz
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Abstract

We propose and demonstrate a method for measuring the joint spectrum of photon pairs via Fourier spectroscopy. The biphoton spectral intensity is computed from a two-dimensional interferogram of coincidence counts. The method has been implemented for a type-I downconversion source using a pair of common-path Mach-Zender interferometers based on Soleil compensators. The experimental results agree well with calculated frequency correlations that take into account the effects of coupling into single-mode fibers. The Fourier method is advantageous over scanning spectrometry when detectors exhibit high dark count rates leading to dominant additive noise.

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Wojciech Wasilewski, Piotr Wasylczyk, Piotr Kolenderski, Konrad Banaszek, Czeslaw Radzewicz. 2005-12-05. Joint spectrum of photon pairs measured by coincidence Fourier spectroscopy. https://doi.org/10.1364/ol.31.001130

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