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arXiv · 2403.12866

Purifying photon indistinguishability through quantum interference

Carlos F. D. Faurby·Lorenzo Carosini·Huan Cao·Patrik I. Sund·Lena M. Hansen·Francesco Giorgino·Andrew B. Villadsen·Stefan N. van den Hoven·Peter Lodahl·Stefano Paesani·Juan C. Loredo·Philip Walther
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Abstract

Indistinguishability between photons is a key requirement for scalable photonic quantum technologies. We experimentally demonstrate that partly distinguishable single photons can be purified to reach near-unity indistinguishability by the process of quantum interference with ancillary photons followed by heralded detection of a subset of them. We report on the indistinguishability of the purified photons by interfering two purified photons and show improvements in the photon indistinguishability of $2.774(3)$\% in the low-noise regime, and as high as $10.2(5)$ \% in the high-noise regime.

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Carlos F. D. Faurby, Lorenzo Carosini, Huan Cao, Patrik I. Sund, Lena M. Hansen, Francesco Giorgino, Andrew B. Villadsen, Stefan N. van den Hoven, Peter Lodahl, Stefano Paesani, Juan C. Loredo, Philip Walther. 2024-03-19. Purifying photon indistinguishability through quantum interference. https://arxiv.org/abs/2403.12866

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