We report new, to the best of our knowledge, advances in Fabry–Perot Bragg grating nanoresonators on low-loss silicon nitride (Si3N4). Building on a previous demonstration of an intrinsic quality factor Qinof 19.3 million with 1.4 dB/m propagation loss, we now achieve Qinup to 121 million on a 100-nm Si3N4platform with an ultralow propagation loss of 0.19 dB/m. Even on a 300-nm Si3N4platform, Qinof 58 million is obtained with 0.45 dB/m loss. Crucially, an advanced tapered grating design is introduced to minimize mode mismatch between the waveguide and Bragg mirror. These improvements pave the way for compact ultrahigh-Q photonic integrated resonators for applications in nonlinear optics and precision photonics.
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Twenty-nine million intrinsic Q -factor monolithic microresonators on thin-film lithium niobate
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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- Award ID(s):
- 2137723
- PAR ID:
- 10563695
- Publisher / Repository:
- Optica
- Date Published:
- Journal Name:
- Photonics Research
- Volume:
- 12
- Issue:
- 8
- ISSN:
- 2327-9125
- Page Range / eLocation ID:
- A63
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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