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Updated: Jun 4, 2026
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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
Electrooptic jumps in natural helicoidal photonic bandgap structures.
Karen Allahverdyan1, Tigran Galstian
1Center for Optics, Photonics and Laser, Department of Physics, Engineering Physics and Optics, Laval University, Pav. d'Optique-Photonique, Québec, Canada.
Optics Express
|March 4, 2011
Summary
Researchers used an electric field to induce self-adaptation and pitch jumps in cholesteric liquid crystal photonic bandgap structures. This study observed dynamic spectral and morphological changes under fixed deformation conditions.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Optoelectronics
Background:
- Cholesteric liquid crystals exhibit unique photonic bandgap properties.
- Electric fields can influence liquid crystal structures.
- Photonic bandgap structures are crucial for optical device applications.
Purpose of the Study:
- To investigate self-adaptation and pitch jumps in helicoidal photonic bandgap structures.
- To explore the effect of electric fields on cholesteric liquid crystals.
- To analyze dynamic spectral and morphological changes during structural transitions.
Main Methods:
- Utilizing a strong electromechanical effect to induce structural changes.
- Employing a cholesteric liquid crystal with negative dielectric anisotropy.
- Using a very thin substrate to facilitate significant thickness changes.
- Performing spectral and morphological analyses during dynamic jumps.
Main Results:
- Successfully generated and studied self-adaptation and pitch jumps.
- Observed multiple dynamic jumps under fixed deformation conditions.
- Demonstrated the stabilization of the structure by the electric field.
- Characterized spectral and morphological properties during jumps.
Conclusions:
- The electromechanical effect is effective in controlling liquid crystal photonic bandgap structures.
- Electric field-induced stabilization and thickness changes are key to observing dynamic jumps.
- This research provides insights into the dynamic behavior of cholesteric liquid crystals for photonic applications.
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