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arXiv · 1612.04173

Phonon limit to simultaneous near-unity efficiency and indistinguishability in semiconductor single photon sources

Jake Iles-Smith·Dara P. S. McCutcheon·Ahsan Nazir·Jesper Mørk
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Abstract

Semiconductor quantum dots have recently emerged as a leading platform to efficiently generate highly indistinguishable photons, and this work addresses the timely question of how good these solid-state sources can ultimately be. We establish the crucial role of lattice relaxation in these systems in giving rise to trade-offs between indistinguishability and efficiency. We analyse the two source architectures most commonly employed: a quantum dot embedded in a waveguide and a quantum dot coupled to an optical cavity. For waveguides, we demonstrate that the broadband Purcell effect results in a simple inverse relationship, where indistinguishability and efficiency cannot be simultaneously increased. For cavities, the frequency selectivity of the Purcell enhancement results in a more subtle trade-off, where indistinguishability and efficiency can be simultaneously increased, though by the same mechanism not arbitrarily, limiting a source with near-unity indistinguishability ($>99$\%) to an efficiency of approximately 96\% for realistic parameters.

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Jake Iles-Smith, Dara P. S. McCutcheon, Ahsan Nazir, Jesper Mørk. 2019-07-17. Phonon limit to simultaneous near-unity efficiency and indistinguishability in semiconductor single photon sources. https://doi.org/10.1038/nphoton.2017.101

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