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Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
Published on: September 26, 2014
Polarization-universal bandgap in periodically twisted nematics
Hakob Sarkissian1, Boris Ya Zeldovich, Nelson V Tabiryan
1College of Opitcs and Photonics/CREOL, University of Central Florida, Florida 32816-2700, USA. hakob@creol.ucf.edu
Optics Letters
|May 12, 2006
Summary
Periodically twisted nematic liquid crystals offer tunable bandgap properties and reflect all light polarizations. These novel structures present advantages over cholesteric liquid crystals for various applications.
Area of Science:
- Materials Science
- Optics
- Condensed Matter Physics
Background:
- Cholesteric liquid crystals exhibit selective reflection based on circular polarization.
- Understanding light-matter interactions in liquid crystal structures is crucial for optical applications.
Purpose of the Study:
- To propose and analyze periodically twisted nematic liquid crystals as an alternative to cholesterics.
- To investigate the bandgap and polarization properties of these novel liquid crystal structures.
Main Methods:
- Theoretical analysis of two distinct modulation profiles: sinusoidal and rectangular.
- Comparison of the bandgap and polarization characteristics with conventional cholesteric liquid crystals.
Main Results:
- Periodically twisted nematic liquid crystals possess a tunable bandgap.
- These structures exhibit strong reflection for all polarizations of normally incident light.
- The maximum bandgap is approximately half that of cholesterics for both modulation profiles.
Conclusions:
- Periodically twisted nematic liquid crystals offer unique polarization-independent reflection properties.
- The tunable bandgap and polarization characteristics suggest potential advantages over cholesterics in specific applications.
- Further research into these structures could lead to advancements in optical devices.
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