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Fabrication of 1-D Photonic Crystal Cavity on a Nanofiber Using Femtosecond Laser-induced Ablation
Published on: February 25, 2017
Photonic crystal fibers with squeezed hexagonal lattice
Optics Express
|May 29, 2009
Summary
Researchers studied birefringence in photonic crystal fibers (PCFs). They discovered wavelength-dependent sign changes in form birefringence and proposed a novel PCF polarization splitter.
Area of Science:
- Optics and Photonics
- Materials Science
Background:
- Photonic crystal fibers (PCFs) offer unique light-guiding properties.
- Birefringence and polarization coupling are key characteristics for optical devices.
- Squeezed hexagonal lattices in PCFs present novel structural possibilities.
Purpose of the Study:
- To investigate the birefringence and polarization coupling in index-guiding PCFs with a squeezed hexagonal crystal lattice.
- To explore the phenomenon of wavelength-dependent sign changes in form birefringence.
- To propose and analyze a PCF-based polarization splitter utilizing this unique lattice structure.
Main Methods:
- Numerical simulations and theoretical analysis of light propagation in PCFs.
- Modeling of electromagnetic fields and optical properties within the squeezed hexagonal lattice.
- Design and characterization of a polarization splitter based on the investigated PCF structure.
Main Results:
- Demonstrated that the sign of form birefringence in these PCFs can be altered by changing the wavelength.
- Reported the first observation of wavelength-dependent sign changes in form birefringence for such PCFs.
- Achieved excellent extinction ratios with the proposed PCF polarization splitter.
Conclusions:
- The study reveals a novel characteristic of form birefringence in squeezed hexagonal lattice PCFs.
- The proposed PCF polarization splitter offers a simpler structure and superior performance compared to existing devices.
- This research contributes to the development of advanced optical components for polarization control.
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