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arXiv · 2007.04330

Bright Polarized Single-Photon Source Based on a Linear Dipole

S. E. Thomas·M. Billard·N. Coste·S. C. Wein·Priya·H. Ollivier·O. Krebs·L. Tazaïrt·A. Harouri·A. Lemaitre·I. Sagnes·C. Anton·L. Lanco·N. Somaschi·J. C. Loredo·P. Senellart
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Abstract

Semiconductor quantum dots in cavities are promising single-photon sources. Here, we present a path to deterministic operation, by harnessing the intrinsic linear dipole in a neutral quantum dot via phonon-assisted excitation. This enables emission of fully polarized single photons, with a measured degree of linear polarization up to 0.994 $\pm$ 0.007, and high population inversion -- 85\% as high as resonant excitation. We demonstrate a single-photon source with a polarized first lens brightness of 0.50 $\pm $ 0.01, a single-photon purity of 0.954 $\pm$ 0.001 and single-photon indistinguishability of 0.909 $\pm$ 0.004.

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S. E. Thomas, M. Billard, N. Coste, S. C. Wein, Priya, H. Ollivier, O. Krebs, L. Tazaïrt, A. Harouri, A. Lemaitre, I. Sagnes, C. Anton, L. Lanco, N. Somaschi, J. C. Loredo, P. Senellart. 2020-07-08. Bright Polarized Single-Photon Source Based on a Linear Dipole. https://doi.org/10.1103/physrevlett.126.233601

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