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Mid-wave infrared narrow bandwidth guided mode resonance notch filter
Optics Letters
|January 13, 2017
Summary
We developed a new guided mode resonance notch filter for the mid-wave infrared (MWIR) spectrum. This filter achieves an ultra-narrow transmission notch with high extinction, ideal for laser applications.
Area of Science:
- Optics and Photonics
- Infrared Spectroscopy
- Materials Science
Background:
- The mid-wave infrared (MWIR) spectrum is crucial for various technologies.
- Developing narrow-band filters for the MWIR region presents significant challenges.
Purpose of the Study:
- To design, fabricate, and characterize a novel guided mode resonance notch filter.
- To operate effectively within the technologically vital MWIR region.
Main Methods:
- Guided mode resonance filter design and fabrication.
- Optical characterization using angle- and polarization-dependent Fourier transform infrared spectroscopy.
- Rigorous coupled-wave analysis (RCWA) for simulation and mode identification.
Main Results:
- Achieved a bandstop at approximately 4.1 μm with 12 dB extinction.
- Demonstrated high transmission background (>80%) and low on-resonance transmission (<6%).
- Obtained an ultra-narrow bandwidth transmission notch of 10 cm⁻¹.
- Excellent agreement between experimental results and RCWA simulations.
Conclusions:
- The developed filter exhibits promising performance for MWIR applications.
- RCWA simulations successfully identified the optical modes responsible for the filter's performance.
- The presented structure offers a viable pathway for creating narrow-band laser filters in the MWIR spectrum.
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