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arXiv · 1710.02490

On-demand semiconductor source of 780 nm single photons with controlled temporal wave packets

Lucas Béguin·Jan-Philipp Jahn·Janik Wolters·Marcus Reindl·Rinaldo Trotta·Armando Rastelli·Fei Ding·Yongheng Huo·Oliver G. Schmidt·Philipp Treutlein·Richard J. Warburton
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Abstract

We report on a fast, bandwidth-tunable single-photon source based on an epitaxial GaAs quantum dot. Exploiting spontaneous spin-flip Raman transitions, single photons at $780\,$nm are generated on-demand with tailored temporal profiles of durations exceeding the intrinsic quantum dot lifetime by up to three orders of magnitude. Second-order correlation measurements show a low multi-photon emission probability ($g^{2}(0)\sim\,0.10-0.15$) at a generation rate up to $10\,$MHz. We observe Raman photons with linewidths as low as $200\,$MHz, narrow compared to the $1.1\,$GHz linewidth measured in resonance fluorescence. The generation of such narrow-band single photons with controlled temporal shapes at the rubidium wavelength is a crucial step towards the development of an optimized hybrid semiconductor-atom interface.

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Lucas Béguin, Jan-Philipp Jahn, Janik Wolters, Marcus Reindl, Rinaldo Trotta, Armando Rastelli, Fei Ding, Yongheng Huo, Oliver G. Schmidt, Philipp Treutlein, Richard J. Warburton. 2017-10-06. On-demand semiconductor source of 780 nm single photons with controlled temporal wave packets. https://doi.org/10.1103/physrevb.97.205304

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