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Updated: May 12, 2026
12:18
Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Coupling modulation of microrings at rates beyond the linewidth limit
W D Sacher1, W M J Green, S Assefa
1Department of Electrical and Computer Engineering and Institute for Optical Sciences, University of Toronto, 10 King’s College Road, Toronto, Ontario, M5S 3G4, Canada. wesley.sacher@mail.utoronto.ca
Optics Express
|April 24, 2013
Summary
Silicon microring resonators overcome speed limits using coupling modulation, achieving over twice the data rate of traditional methods. This innovation offers a path to simultaneously low-power and high-speed optical modulators.
Area of Science:
- Photonics and optical engineering
- Integrated silicon photonics
- Modulator technology
Background:
- Conventional resonant modulators are limited by cavity linewidth, restricting modulation speeds.
- Achieving high-speed and low-power operation simultaneously in resonant modulators is a significant challenge.
Purpose of the Study:
- To demonstrate optical modulation rates exceeding conventional cavity linewidth limits.
- To explore the potential of silicon coupling modulated microrings for high-speed, low-power optical communication.
Main Methods:
- Utilized a silicon coupling modulated microring resonator.
- Performed small-signal measurements to assess modulation rates relative to cavity linewidth.
- Conducted eye diagram measurements to evaluate data rates.
Main Results:
- Coupling modulation demonstrated rates at least 6x the cavity linewidth, free from parasitic limitations.
- Achieved data rates more than twice that of conventional intracavity phase modulation.
- Proposed DC-balanced encoding to mitigate inter-symbol interference.
Conclusions:
- Coupling modulation offers a viable strategy to surpass traditional speed limitations in resonant modulators.
- This technique enables high-Q resonators to achieve both high speed and low power, overcoming previous trade-offs.
- The findings pave the way for more efficient and faster optical communication systems.
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