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Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters
Published on: February 4, 2018
Experimental determination of coupled microring filter parameters via pole-zero extraction
Ashok M Prabhu1, Hai Ling Liew, Vien Van
1Department of Electrical and Computer Engineering, University of Alberta, Edmonton, AB, Canada. ashok.prabhu@ualberta.ca
Optics Express
|September 17, 2008
Summary
A new method extracts key parameters of microring resonator filters directly from measured responses. This aids in understanding fabrication and refining filter performance.
Area of Science:
- Photonics and optical engineering
- Integrated optics
- Microring resonator devices
Background:
- Serially-coupled microring resonator filters are crucial optical components.
- Accurate device parameter extraction is essential for performance optimization.
- Existing methods may be indirect or complex.
Purpose of the Study:
- To present a direct method for extracting critical parameters of N(th)-order serially-coupled microring resonator filters.
- To validate the method using a microring doublet on a Silicon-on-Insulator platform.
- To demonstrate the utility of extracted parameters for fabrication analysis and device trimming.
Main Methods:
- Extraction of coupling coefficients, resonant frequency detunings, and loss from power spectral responses.
- Construction of the through-port complex transfer function using experimentally extracted poles and zeros.
- Application of the method to a symmetric microring doublet.
Main Results:
- Successful direct extraction of device parameters.
- Good agreement between simulated spectral responses (using extracted parameters) and measured data.
- Demonstrated correlation between extracted parameters, poles/zeros, and fabrication quality.
Conclusions:
- The presented method provides direct and accurate extraction of microring resonator filter parameters.
- Extracted parameters offer valuable insights into the fabrication process.
- The method can guide post-fabrication trimming for improved high-order microring filter performance.
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