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arXiv · 2304.11676

Quantum correlated photons via a passive nonlinear microcavity

Mengdi Zhao·Yunkai Wang·Shanhui Fan·Kejie Fang
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Abstract

Photons, by nature, typically do not exhibit interactions with each other. Creating photon-photon interactions holds immense importance in both fundamental physics and quantum technologies. Currently, such interactions have only been achieved indirectly as mediated by atomic-like quantum emitters with resonant photon-atom interactions. However, the use of these indirect interactions presents substantial fundamental challenges that impede scaling and practical applications. Here we demonstrate creation of non-classical photon correlations, including photon anti-bunching, via a passive InGaP photonic integrated circuit. Our approach employs the quantum interference between uncorrelated light and the two-photon bound state, the latter of which arises from the $\chi^{(2)}$-mediated photon interaction. Our work opens a new route in controlling quantum light by harnessing highly-engineerable bulk optical nonlinearities, which has significant implications for nonlinear optical quantum information processing and quantum networking.

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Mengdi Zhao, Yunkai Wang, Shanhui Fan, Kejie Fang. 2023-04-23. Quantum correlated photons via a passive nonlinear microcavity. https://arxiv.org/abs/2304.11676

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