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Title: Toward 1% single-photon anharmonicity with periodically poled lithium niobate microring resonators

The absence of the single-photon nonlinearity has been a major roadblock in developing quantum photonic circuits at optical frequencies. In this paper, we demonstrate a periodically poled thin film lithium niobate microring resonator (PPLNMR) that reaches 5,000,000%/W second-harmonic conversion efficiency—almost 20-fold enhancement over the state-of-the-art—by accessing its largestχ<#comment/>(2)tensor componentd33via quasi-phase matching. The corresponding single-photon coupling rateg/2π<#comment/>is estimated to be 1.2 MHz, which is an important milestone as it approaches the dissipation rateκ<#comment/>/2π<#comment/>of best-available lithium niobate microresonators developed in the community. Using a figure of merit defined asg/κ<#comment/>, our device reaches a single-photon nonlinear anharmonicity approaching 1%. We show that, by further scaling of the device, it is possible to improve the single-photon anharmonicity to a regime where photon blockade effect can be manifested.

Authors:
; ; ; ;
Publication Date:
NSF-PAR ID:
10202472
Journal Name:
Optica
Volume:
7
Issue:
12
Page Range or eLocation-ID:
Article No. 1654
ISSN:
2334-2536
Publisher:
Optical Society of America
Sponsoring Org:
National Science Foundation
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