arXiv:2210.12833 · Nano Letters

Position-Controlled Telecom Single Photon Emitters Operating at Elevated Temperatures

Patrick Laferrière, S. Haffouz, David B. Northeast, Philip J. Poole, Robin L. Williams, Dan Dalacu

Published Jan 27, 2023• 21 citations

Abstract

High Resolution Image Download MS PowerPoint Slide A key resource in quantum-secured communication protocols are single photon emitters. For long-haul optical networks, it is imperative to use photons at wavelengths compatible with telecom single mode fibers. We demonstrate high purity single photon emission at 1.31 μm using deterministically positioned InP photonic waveguide nanowires containing single InAsP quantum dot-in-a-rod structures. At excitation rates that saturate the emission, we obtain a single photon collection efficiency at first lens of 27.6% and a probability of multiphoton emission of 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, 220 and 300 K, respectively, which is attributed to an overlap of temperature-broadened excitonic emission lines. These results are a promising step toward scalably fabricating telecom single photon emitters that operate under relaxed cooling requirements.

DOI: 10.1021/acs.nanolett.2c04375

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