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arXiv · 2210.12833

Position-controlled Telecom Single Photon Emitters Operating at Elevated Temperatures

Patrick Laferrière·Sofiane Haffouz·David B. Northeast·Philip J. Poole·Robin L. Williams·Dan Dalacu
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Abstract

Single photon emitters are a key component for enabling the practical use of quantum key distribution protocols for secure communications. For long-haul optical networks it is imperative to use photons at wavelengths that are compatible with standard single mode fibers: 1.31 {\mu}m and 1.55 {\mu}m. We demonstrate high purity single photon emission at 1.31 {\mu}m using deterministically positioned InP photonic waveguide nanowires containing single InAsP quantum dot-in-a-rod structures. At 4 K the detected count rate in fiber was 1.9 Mcps under above-band pulsed laser excitation at 80 MHz corresponding to a single photon collection efficiency at the first lens of 25%. At this count rate, the probability of multiphoton emission is g(2)(0) = 0.021. We have also evaluated the performance of the source as a function of temperature. Multiphoton emission probability increases with temperature with values of 0.11, 0.34 and 0.57 at 77 K, 220 K and 300 K, respectively, which is attributed to an overlap of temperature-broadened excitonic emission lines. These results are a promising step towards scalably fabricating telecom single photon emitters that operate under relaxed cooling requirements.

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Patrick Laferrière, Sofiane Haffouz, David B. Northeast, Philip J. Poole, Robin L. Williams, Dan Dalacu. 2022-10-23. Position-controlled Telecom Single Photon Emitters Operating at Elevated Temperatures. https://doi.org/10.1021/acs.nanolett.2c04375

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