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Spectral density matrix of a single photon measured

Wojciech Wasilewski·Piotr Kolenderski·Robert Frankowski
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Abstract

We propose and demonstrate a method for measuring the spectral density matrix of a single photon pulse. The method is based on registering Hong-Ou-Mandel interference between photon to be measured and a pair of attenuated and suitably delayed laser pulses described by a known spectral amplitude. The density matrix is retrieved from a two-dimensional interferogram of coincidence counts. The method has been implemented for a type-I downconversion source, pumped by ultrashort laser pulses. The experimental results agree well with a theoretical model which takes into account the temporal as well as spatial effects in the source.

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Wojciech Wasilewski, Piotr Kolenderski, Robert Frankowski. 2007-02-21. Spectral density matrix of a single photon measured. https://doi.org/10.1103/physrevlett.99.123601

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