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Fabrication and Characterization of High-Q Silicon Nitride Membrane Resonators
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Resonance-splitting and enhanced notch depth in SOI ring resonators with mutual mode coupling
Ziyang Zhang1, Matteo Dainese, Lech Wosinski
1Laboratory of Optics, Photonics and Quantum Electronics, Department of Microelectronics and Applied Physics, Royal Institute of Technology (KTH), Electrum 229, 164 40 Kista, Sweden.
Optics Express
|June 11, 2008
Summary
Mutual mode coupling in silicon-on-insulator micro-ring resonators enhances notch depth and resonance splitting. This advancement shows promise for improved bio-sensing applications.
Area of Science:
- Photonics and Optical Engineering
- Materials Science
Background:
- Micro-ring resonators are key components in integrated photonics.
- Controlling light-matter interactions in these devices is crucial for advanced functionalities.
Purpose of the Study:
- To experimentally demonstrate resonance-splitting and enhanced notch depth in micro-ring resonators.
- To investigate the effects of mutual mode coupling on resonator performance.
- To explore the potential of these enhanced resonators for bio-sensing.
Main Methods:
- Fabrication of micro-ring resonators on a silicon-on-insulator (SOI) platform.
- Inducing mutual mode coupling via nanometer-scaled gratings or evanescent directional coupling between concentric rings.
- Characterization of transmission spectra.
- Fitting experimental data using time-domain coupled mode analysis.
Main Results:
- Demonstrated resonance-splitting of 0.68 nm in a 5-microm-radius ring.
- Achieved a notch depth of 40 dB in a 10-microm-radius ring.
- Obtained an intrinsic Q factor of 2.6 x 10^5 for a 20-microm-radius ring.
- Notch depth improvement exceeding 25 dB in a 40-39-microm-radius double-ring structure.
Conclusions:
- Mutual mode coupling effectively enhances notch depth and resonance splitting in SOI micro-ring resonators.
- Concentric ring structures offer significant improvements in notch depth and modal area.
- These enhanced optical properties present promising advantages for future bio-sensing applications.
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