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Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters
Published on: February 4, 2018
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Tunable filter using ferroelectric-dielectric periodic multilayer
Applied Optics
|May 14, 2015
Summary
This study demonstrates a tunable photonic crystal filter with a 35% frequency tuning achieved using an 8 V/micron voltage. The filter
Area of Science:
- Photonics and optical engineering.
- Materials science.
Background:
- Photonic crystals offer unique light manipulation properties.
- Tunable filters are crucial for optical communication and sensing.
Purpose of the Study:
- To theoretically investigate the microwave optical properties of a tunable photonic crystal filter.
- To analyze the impact of external voltage, structural parameters, and incident light characteristics on filter performance.
Main Methods:
- Transfer matrix method.
- Finite difference time domain (FDTD) method.
- Plane wave expansion (PWE) method.
Main Results:
- Achieved approximately 35% frequency tuning with an 8 V/micron applied voltage.
- Demonstrated a direct proportionality between the number of transmission peaks and the number of photonic crystal periods (N).
- Identified that filtering frequency remains invariant to the angle of incidence and polarization.
Conclusions:
- The proposed photonic crystal structure enables effective voltage-tunable filtering in the microwave regime.
- The number of transmission peaks can be controlled by adjusting the photonic crystal's periodicity.
- The filter exhibits robust performance insensitive to variations in incidence angle and polarization.
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