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arXiv · 2010.11817

Maximally entangled and GHz-clocked on-demand photon pair source

Caspar Hopfmann·Weijie Nie·Nand Lal Sharma·Carmen Weigelt·Fei Ding·Oliver G. Schmidt
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Abstract

We present a 1 GHz-clocked, maximally entangled and on-demand photon pair source based on droplet etched GaAs quantum dots using two-photon excitation. By employing these GaP microlensenhanced devices in conjunction with their substantial brightness, raw entanglement fidelities of up to $0.95 \pm 0.01$ and post-selected photon indistinguishabilities of up to $0.93 \pm 0.01$, the suitability for quantum repeater based long range quantum entanglement distribution schemes is shown. Comprehensive investigations of a complete set of polarization selective two-photon correlations as well as time resolved Hong-Ou-Mandel interferences facilitate innovative methods that determine quantities such as photon extraction and excitation efficiencies as well as pure dephasing directly - opposed to commonly employed indirect techniques.

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Caspar Hopfmann, Weijie Nie, Nand Lal Sharma, Carmen Weigelt, Fei Ding, Oliver G. Schmidt. 2020-10-22. Maximally entangled and GHz-clocked on-demand photon pair source. https://doi.org/10.1103/physrevb.103.075413

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