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arXiv · 2501.15970

Two-Photon Interference from an InAs Quantum Dot emitting in the Telecom C-Band

Jaewon Kim·Jochen Kaupp·Yorick Reum·Giora Peniakov·Johannes Michl·Felix Kohr·Monika Emmerling·Martin Kamp·Yong-Hoon Cho·Tobias Huber-Loyola·Sven Höfling·Andreas T. Pfenning
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Abstract

Two-photon interference from an InAs/InAlGaAs quantum dot (QD) emitting in the telecom C-band with a raw two-photon interference visibility of $V_{HOM}=(71.9\pm0.2)$ % is demonstrated. This is achieved by a two-fold approach: an improvement of the molecular beam epitaxial growth for better QDs, and integration of the QDs into an optical circular Bragg grating resonator for a Purcell enhancement of the radiative decay rate. The quantum optical properties of the fabricated device are studied by means of time-correlated single-photon counting under quasi-resonant excitation of the charged exciton line. A reduced lifetime of $T_1=(257.5\pm0.2)$ ps is found corresponding to a Purcell factor of $F_P\geqq(4.7\pm0.5)$. Pronounced anti-bunching of the second-order autocorrelation function at zero time delay $g^{(2)} (0)=(0.0307\pm0.0004)$ confirms the single-photon emission character. The two-photon interference is demonstrated with an unbalanced Mach-Zehnder interferometer in Hong-Ou-Mandel configuration. We discuss strategies how to further improve the indistinguishability, and provide a survey of the state-of-the art.

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Jaewon Kim, Jochen Kaupp, Yorick Reum, Giora Peniakov, Johannes Michl, Felix Kohr, Monika Emmerling, Martin Kamp, Yong-Hoon Cho, Tobias Huber-Loyola, Sven Höfling, Andreas T. Pfenning. 2025-01-27. Two-Photon Interference from an InAs Quantum Dot emitting in the Telecom C-Band. https://doi.org/10.1002/qute.202500069

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