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arXiv · 1712.06937

On-demand generation of background--free single photons from a solid-state source

Lucas Schweickert·Klaus D. Jöns·Katharina D. Zeuner·Saimon Filipe Covre da Silva·Huiying Huang·Thomas Lettner·Marcus Reindl·Julien Zichi·Rinaldo Trotta·Armando Rastelli·Val Zwiller
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Abstract

True on--demand high--repetition--rate single--photon sources are highly sought after for quantum information processing applications. However, any coherently driven two-level quantum system suffers from a finite re-excitation probability under pulsed excitation, causing undesirable multi--photon emission. Here, we present a solid--state source of on--demand single photons yielding a raw second--order coherence of $g^{(2)}(0)=(7.5\pm1.6)\times10^{-5}$ without any background subtraction nor data processing. To this date, this is the lowest value of $g^{(2)}(0)$ reported for any single--photon source even compared to the previously best background subtracted values. We achieve this result on GaAs/AlGaAs quantum dots embedded in a low--Q planar cavity by employing (i) a two--photon excitation process and (ii) a filtering and detection setup featuring two superconducting single--photon detectors with ultralow dark-count rates of $(0.0056\pm0.0007) s^{-1}$ and $(0.017\pm0.001) s^{-1}$, respectively. Re--excitation processes are dramatically suppressed by (i), while (ii) removes false coincidences resulting in a negligibly low noise floor.

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Lucas Schweickert, Klaus D. Jöns, Katharina D. Zeuner, Saimon Filipe Covre da Silva, Huiying Huang, Thomas Lettner, Marcus Reindl, Julien Zichi, Rinaldo Trotta, Armando Rastelli, Val Zwiller. 2018-10-15. On-demand generation of background--free single photons from a solid-state source. https://doi.org/10.1063/1.5020038

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