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arXiv · 1109.6254

Coalescence of Single Photons Emitted by Disparate Single Photon Sources: The Example of InAs Quantum Dots and Parametric Down-Conversion Sources

Sergey V. Polyakov·Andreas Muller·Edward B. Flagg·Alex Ling·Natalia Borjemscaia·Edward Van Keuren·Alan Migdall·Glenn S. Solomon
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Abstract

Single photons produced by fundamentally dissimilar physical processes will in general not be indistinguishable. We show how photons produced from a quantum dot and by parametric down-conversion in a nonlinear crystal can be manipulated to be indistinguishable. The measured two-photon coalescence probability is 16%, and is limited by quantum-dot decoherence. Temporal filtering to the quantum dot coherence time and accounting for detector time response increases this to 61% while retaining 25% of the events. This technique can connect different elements in a scalable quantum network.

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Sergey V. Polyakov, Andreas Muller, Edward B. Flagg, Alex Ling, Natalia Borjemscaia, Edward Van Keuren, Alan Migdall, Glenn S. Solomon. 2011-09-28. Coalescence of Single Photons Emitted by Disparate Single Photon Sources: The Example of InAs Quantum Dots and Parametric Down-Conversion Sources. https://doi.org/10.1103/physrevlett.107.157402

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