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 largest
Properly interpreting lidar (light detection and ranging) signal for characterizing particle distribution relies on a key parameter,
- NSF-PAR ID:
- 10372000
- Publisher / Repository:
- Optical Society of America
- Date Published:
- Journal Name:
- Applied Optics
- Volume:
- 59
- Issue:
- 10
- ISSN:
- 1559-128X; APOPAI
- Page Range / eLocation ID:
- Article No. C31
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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tensor component via quasi-phase matching. The corresponding single-photon coupling rate is estimated to be 1.2 MHz, which is an important milestone as it approaches the dissipation rate of best-available lithium niobate microresonators developed in the community. Using a figure of merit defined as , 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. -
Materials with strong second-order (
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