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The recent emergence of thin-film lithium niobate (TFLN) has extended the landscape of integrated photonics. This has been enabled by the commercialization of TFLN wafers and advanced nanofabrication of TFLN such as high-quality dry etching. However, fabrication imperfections still limit the propagation loss to a few dB/m, restricting the impact of this platform. Here, we demonstrate TFLN microresonators with a record-high intrinsic quality (Q) factor of twenty-nine million, corresponding to an ultra-low propagation loss of 1.3 dB/m. We present spectral analysis and the statistical distribution ofQfactors across different resonator geometries. Our work pushes the fabrication limits of TFLN photonics to achieve aQfactor within 1 order of magnitude of the material limit.
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High Q, Compact Photonic Crystal Nanobeam Cavity for an Active Device Platform in a CMOS Silicon Photonics Process
We demonstrate a high Q, compact photonic crystal nanobeam cavity in the new 45nm GlobalFoundries 45CLO monolithic electronics-photonics platform optimized for silicon photonics – with an intrinsic Q of 134,000, FSR of 24.17 nm, and a theoretical Q/V of 2.2E-5 (λ/n)^(-3).
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- Award ID(s):
- 2023751
- PAR ID:
- 10354873
- Date Published:
- Journal Name:
- 2021 IEEE 17th International Conference on Group IV Photonics (GFP)
- Page Range / eLocation ID:
- 1 to 2
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/GFP51802.2021.9673876
