Efficient fiber-pigtailed source of indistinguishable single photons

Nico Margaria; Florian Pastier; Thinhinane Bennour; Marie Billard; Edouard Ivanov; William Hease; Petr Stepanov; Albert F. Adiyatullin; Raksha Singla; Mathias Pont; Maxime Descampeaux; Alice Bernard; Anton Pishchagin; Martina Morassi; Aristide Lemaître; Thomas Volz; Valérian Giesz; Niccolo Somaschi; Nicolas Maring; Sébastien Boissier; Thi Huong Au; Pascale Senellart

arXiv · 2410.07760

Efficient fiber-pigtailed source of indistinguishable single photons

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Abstract

Semiconductor quantum dots in microcavities are an excellent platform for the efficient generation of indistinguishable single photons. However, their use in a wide range of quantum technologies requires their controlled fabrication and integration in compact closed-cycle cryocoolers, with a key challenge being the efficient and stable extraction of the single photons into a single-mode fiber. Here we report on a novel method for fiber-pigtailing of deterministically fabricated single-photon sources. Our technique allows for nanometer-scale alignment accuracy between the source and a fiber, alignment that persists all the way from room temperature to 2.4 K. We demonstrate high performance of the device under near-resonant optical excitation with g$^{(2)}$(0) = 1.3 %, a photon indistinguishability of 97.5 % and a fibered brightness of 20.8 %. We show that the indistinguishability and single-photon rate are stable for over ten hours of continuous operation in a single cooldown. We further confirm that the device performance is not degraded by nine successive cooldown-warmup cycles.

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Nico Margaria, Florian Pastier, Thinhinane Bennour, Marie Billard, Edouard Ivanov, William Hease, Petr Stepanov, Albert F. Adiyatullin, Raksha Singla, Mathias Pont, Maxime Descampeaux, Alice Bernard, Anton Pishchagin, Martina Morassi, Aristide Lemaître, Thomas Volz, Valérian Giesz, Niccolo Somaschi, Nicolas Maring, Sébastien Boissier, Thi Huong Au, Pascale Senellart. 2024-10-10. Efficient fiber-pigtailed source of indistinguishable single photons. https://arxiv.org/abs/2410.07760

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