@article{73d7f1cd4b9844d5b871914176d688b5,
title = "Ultra-High-Q Racetrack Resonators on Thick SOI Platform through Hydrogen Annealing Smoothing",
abstract = "We implemented a hydrogen annealing based post-processing technique as a tool to improve the sidewall roughness of 3 μm thick silicon-on-insulator (SOI) waveguides and demonstrated ultra-high- Q factors on racetrack resonators leveraging on the propagation loss reduction achieved through the smoothing process. The designed racetracks are based on a combination of rib waveguides and strip-waveguide-based Euler bends. We measured intrinsic quality factors of 14×10^6 for a racetrack with a footprint of ∼5.5 mm^2 and 10.7×10^6 for a smaller racetrack with footprint of ∼1.48 mm^2 . The estimated propagation loss for the rib waveguides was ∼2.7 dB/m, representing a ×3 reduction respect to the previously measured losses of 3 μm thick SOI rib waveguides treated with thermal oxidation smoothing. Overall, the post-processing technique allowed to significantly reduce the sidewall roughness without altering the geometry of the waveguides, unlike in sub-micron scale SOI platforms, making it an attractive solution for applications demanding ultra-low losses.",
keywords = "Couplings, Hydrogen annealing, low-loss waveguides, microresonators, optical losses, Optical waveguides, photonic integrated circuits, Propagation losses, Q-factor, resonators, Resonators, Ribs, sidewall roughness, silicon photonics, Strips",
author = "Marin, {Yisbel E.} and Arijit Bera and Matteo Cherchi and Timo Aalto",
note = "Publisher Copyright: Author",
year = "2023",
month = jun,
day = "1",
doi = "10.1109/JLT.2023.3262413",
language = "English",
volume = "41",
pages = "3642 -- 3648",
journal = "Journal of Lightwave Technology",
issn = "0733-8724",
publisher = "IEEE Institute of Electrical and Electronic Engineers",
number = "11",
}