Related Experiment Video
Updated: Jul 2, 2026
09:46
Fabrication and Characterization of High-Q Silicon Nitride Membrane Resonators
Published on: August 8, 2025
Coupled-ring-resonator-based silicon modulator for enhanced performance
Yunchu Li1, Lin Zhang, Muping Song
1Dept of Electrical Engineering, Univ of Southern California, Los Angeles, CA 90089, USA. yunchuli@usc.edu
Optics Express
|August 20, 2008
Summary
A novel silicon coupled-ring modulator achieves high-speed modulation for optical communications. This design offers improved performance, including higher data rates and enhanced dispersion tolerance, making it suitable for advanced photonic systems.
Area of Science:
- Photonics
- Optical Communications
- Integrated Optics
Background:
- Ring modulators are crucial components in optical communication systems.
- Existing designs face limitations in modulation speed, power consumption, and dispersion tolerance.
Purpose of the Study:
- To propose and simulate a compact silicon coupled-ring modulator structure.
- To enhance modulation speed and improve performance metrics for optical modulators.
Main Methods:
- A silicon coupled-ring modulator with one actively driven ring coupled to a waveguide was designed.
- Electromagnetic simulations were performed to analyze the modulator's characteristics.
Main Results:
- The proposed structure enables potentially 60-Gb/s non-return-to-zero (NRZ) modulation with over 20-dB extinction ratio.
- Frequency chirp is adjustable by varying the inter-ring coupling coefficient.
- Dispersion tolerance for a 40-Gb/s NRZ signal is extended from 18 to 85 ps/nm.
Conclusions:
- The compact silicon coupled-ring modulator offers significant advantages for high-speed optical communication.
- The design demonstrates potential for improved data rates, reduced power consumption, and better dispersion tolerance.
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