Narrow-linewidth optical coherent oscillators in ultra-low loss silicon nitride
Licentiate thesis, 2025
As a popular integrated photonic platform, silicon nitride has a significant potential for addressing these challenges since it has high nonlinearity, wide transparent window, and good compatibility with other materials. In our previous work, we have realized low-loss long waveguides and high-Q microring resonators. In this thesis, we further reduce the propagation loss of dispersion-engineered silicon nitride waveguides by smoothing the sidewall roughness. By periodically modulating the intrinsic and extrinsic Q factors of the microring resonator, we achieve an on-chip optical parametric oscillator with an output power of 215 mW and an intrinsic linewidth of 220 Hz. In addition, we suppress the frequency noise of both semiconductor lasers and soliton microsombs using an original self-injection locking method. We reduce the intrinsic linewidth of the semiconductor laser from 818 000 Hz to 135 Hz, and compress the intrinsic linewidth of comb lines of the soliton microcomb to below 1 Hz. These results pave the way for on-chip integration of high-power, narrow-linewidth lasers and optical parametric oscillators.
semiconductor laser
optical parametric oscillator
silicon nitride
narrow linewidth
frequency noise
low loss
integrated photonics
Author
Yi Sun
Chalmers, Microtechnology and Nanoscience (MC2), Photonics
Low-loss dispersion-engineered silicon nitride waveguides coated with a thin blanket layer
Optics InfoBase Conference Papers,;(2022)
Paper in proceeding
Yi Sun, Fuchuan Lei, Yan Gao, and Victor Torres-Company, High-power on-chip hyperparametric oscillator
Self-injection-locked optical parametric oscillator based on microcombs
Optica,;Vol. 11(2024)p. 420-426
Journal article
Narrow-linewidth and tunable parametric oscillator
2024 Conference on Lasers and Electro-Optics, CLEO 2024,;(2024)
Paper in proceeding
Driving Forces
Sustainable development
Innovation and entrepreneurship
Areas of Advance
Nanoscience and Nanotechnology
Subject Categories (SSIF 2025)
Nano-technology
Physical Sciences
Electrical Engineering, Electronic Engineering, Information Engineering
Infrastructure
Myfab (incl. Nanofabrication Laboratory)
Publisher
Chalmers
Kollektorn, A423, MC2
Opponent: Nils Johan Engelsen, Assistant Professor, Quantum Technology, Microtechnology and Nanoscience, Chalmers University of Technology