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arXiv · 2505.01929

Monitoring the generation of photonic linear cluster states with partial measurements

Valentin Guichard·Leonid Vidro·Dario A. Fioretto·Petr Steindl·Daniel Istrati·Yehuda Pilnyak·Mathias Pont·Martina Morassi·Aristide Lemaître·Isabelle Sagnes·Niccolo Somaschi·Nadia Belabas·Hagai Eisenberg·Pascale Senellart
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Abstract

Quantum states of light with many entangled photons are key resources for photonic quantum computing and quantum communication. In this work, we exploit a highly resource-efficient generation scheme based on a linear optical circuit embedding a fibered delay loop acting as a quantum memory. The single photons are generated with a bright single-photon source based on a semiconductor quantum dot, allowing to perform the entangling scheme up to 6 photons. We demonstrate $2$, $3$, $4$ and $6$-photon entanglement generation at respective rates of $6$kHz, $120$Hz, $2.2$Hz, and $2$mHz, corresponding to an average scaling ratio of $46$. We introduce a method for real-time control of entanglement generation based on partially post-selected measurements. The visibility of such measurements carries faithful information to monitor the entanglement process, an important feature for the practical implementation of photonic measurement-based quantum computation.

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Valentin Guichard, Leonid Vidro, Dario A. Fioretto, Petr Steindl, Daniel Istrati, Yehuda Pilnyak, Mathias Pont, Martina Morassi, Aristide Lemaître, Isabelle Sagnes, Niccolo Somaschi, Nadia Belabas, Hagai Eisenberg, Pascale Senellart. 2025-05-03. Monitoring the generation of photonic linear cluster states with partial measurements. https://doi.org/10.1088/2058-9565%2Fae21ff

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