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arXiv · 1801.01672

Quantum dot single photon sources with ultra-low multi-photon probability

Lukas Hanschke·Kevin A. Fischer·Stefan Appel·Daniil Lukin·Jakob Wierzbowski·Shuo Sun·Rahul Trivedi·Jelena Vučković·Jonathan J. Finley·Kai Müller
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Abstract

High-quality sources of single photons are of paramount importance for quantum communication, sensing and metrology. To these ends, resonantly excited two-level systems based on self-assembled quantum dots have recently generated widespread interest. Nevertheless, we have recently shown that for resonantly excited two-level systems, emission of a photon during the presence of the excitation laser pulse and subsequent re-excitation results in a degradation of the obtainable single-photon purity. Here, we demonstrate that generating single photons from self-assembled quantum dots with a scheme based on two-photon excitation of the biexciton strongly suppresses the re-excitation. Specifically, the pulse-length dependence of the multi-photon error rate reveals a quadratic dependence in contrast to the linear dependence of resonantly excited two-level systems, improving the obtainable multi-photon error rate by several orders of magnitude for short pulses. We support our experiments with a new theoretical framework and simulation methodology to understand few-photon sources.

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Lukas Hanschke, Kevin A. Fischer, Stefan Appel, Daniil Lukin, Jakob Wierzbowski, Shuo Sun, Rahul Trivedi, Jelena Vučković, Jonathan J. Finley, Kai Müller. 2018-01-05. Quantum dot single photon sources with ultra-low multi-photon probability. https://doi.org/10.1038/s41534-018-0092-0

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