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arXiv · 2609.24858

Overcoming the Hong-Ou-Mandel interference limitation for the second photon from a two-photon cascade

Raphael Joos·Michal Vyvlecka·Tim Strobel·Benjamin Breiholz·Furkan Aglarci·Ponraj Vijayan·Hans-Georg Babin·Arne Ludwig·Michael Jetter·Simone L. Portalupi·Peter Michler
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Abstract

Quantum emitters such as semiconductor quantum dots can provide entangled photon pairs emitting from a system of cascaded states. However, the resulting temporal correlation between the two photons from the three-level ladder system has been shown to set a limit on the achievable two-photon interference. In this work, we show that such limitation, for photons emitted by the second transition, is only due to reduced temporal overlap at the interference beam splitter. We investigate this theoretically and experimentally by determining time-resolved four-photon coincidences between two successively emitted photon pairs. Post-emission synchronization shows the recovery of maximum interference visibility; in prospective quantum networks this could be achieved via deterministic quantum memories.

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Raphael Joos, Michal Vyvlecka, Tim Strobel, Benjamin Breiholz, Furkan Aglarci, Ponraj Vijayan, Hans-Georg Babin, Arne Ludwig, Michael Jetter, Simone L. Portalupi, Peter Michler. 2026-09-21. Overcoming the Hong-Ou-Mandel interference limitation for the second photon from a two-photon cascade. https://arxiv.org/abs/2609.24858

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