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arXiv · 2105.00275

Photon Conversion and Interaction on Chip

Abstract

The conversion and interaction between quantum signals at a single-photon level are essential for scalable quantum photonic information technology. Using a fully-optimized, periodically-poled lithium niobate microring, we demonstrate ultra-efficient sum-frequency generation on chip. The external quantum efficiency reaches $(65\pm3)\%$ with only $(104\pm4)$ $μ$W pump power, improving the state-of-the-art by over one order of magnitude. At the peak conversion, $3\times10^{-5}$ noise photon is created during the cavity lifetime, which meets the requirement of quantum applications using single-photon pulses. Using pump and signal in single-photon coherent states, we directly measure the conversion probability produced by a single pump photon to be $10^{-5}$ -- breaking the record by 100 times -- and the photon-photon coupling strength to be 9.1 MHz. Our results mark a new milestone toward quantum nonlinear optics at the ultimate single photon limit, creating new background in highly integrated photonics and quantum optical computing.

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Jia-Yang Chen, Zhan Li, Zhaohui Ma, Chao Tang, Heng Fan, Yong Meng Sua, Yu-Ping Huang. 2021-05-01. Photon Conversion and Interaction on Chip. https://arxiv.org/abs/2105.00275

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