Morrison, Christopher L. Rambach, Markus Koong, Zhe Xian Graffitti, Francesco Thorburn, Fiona Kar, Ajoy K. Ma, Yong Park, Suk-In Song, Jin Dong Stoltz, Nick G. Bouwmeester, Dirk Fedrizzi, Alessandro Gerardot, Brian D. 2024-01-19T15:01:15Z 2024-01-19T15:01:15Z 2022-01-10 2021-04 0003-6951 https://pubs.kist.re.kr/handle/201004/117115 On-demand indistinguishable single-photon sources are essential for quantum networking and communication. Semiconductor quantum dots are among the most promising candidates, but their typical emission wavelength renders them unsuitable for use in fiber networks. Here, we present quantum frequency conversion of near-infrared photons from a bright quantum dot to the telecommunication C-band, allowing integration with existing fiber architectures. We use a custom-built, tunable 2400nm seed laser to convert single photons from 942nm to 1550nm in a difference-frequency generation process. We achieve an end-to-end conversion efficiency of similar or equal to 35%, demonstrate count rates approaching 1MHz at 1550nm with g(2)(0) = 0.043(1), and achieve Hong-Ou-Mandel (HOM) visibilities of 60%. We expect this scheme to be preferable to quantum dot sources directly emitting at telecom wavelengths for fiber-based quantum networking. (C) 2021 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/). English American Institute of Physics A bright source of telecom single photons based on quantum frequency conversion Article 10.1063/5.0045413 1 Applied Physics Letters, v.118, no.17 Applied Physics Letters 118 17 N scie scopus 000691325000001 2-s2.0-85104960151 Physics, Applied Physics Article DOT SPIN DOWNCONVERSION telecom single photons quantum frequency conversion InAs quantum dots