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Avoided-crossing-based liquid-crystal photonic-bandgap notch filter
Danny Noordegraaf1, Lara Scolari, Jesper Laegsgaard
1COM-DTU Department of Communications, Optics and Materials, Technical University of Denmark, DK-2800, Denmark. dno@com.dtu.dk
Optics Letters
|May 3, 2008
Summary
We developed a tunable deep notch filter using liquid-crystal photonic-bandgap (LCPBG) fiber. This novel approach exploits avoided crossings for precise spectral tuning without gratings.
Area of Science:
- Photonics
- Optical Engineering
- Materials Science
Background:
- Photonic-crystal fibers (PCFs) offer unique light manipulation properties.
- Liquid crystals (LCs) provide tunable optical characteristics.
- Developing tunable optical filters is crucial for various photonic applications.
Purpose of the Study:
- To demonstrate a highly tunable deep notch filter.
- To realize the filter in a liquid-crystal photonic-bandgap (LCPBG) fiber.
- To investigate the filter's performance using experimental and numerical methods.
Main Methods:
- Filling a solid-core photonic-crystal fiber with a liquid crystal.
- Exploiting avoided crossings within the photonic bandgap.
- Experimental demonstration and numerical simulations.
Main Results:
- A deep notch filter was successfully realized in LCPBG fiber.
- The filter's spectral position was highly tunable.
- The method avoided the need for long-period gratings.
Conclusions:
- A novel and highly tunable deep notch filter was demonstrated.
- This method offers a grating-free approach for filter realization in LCPBG fibers.
- The demonstrated tunability opens possibilities for advanced optical signal processing.
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