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Photonic crystal structures in titanium dioxide (TiO2) and their optimal design
Optics Express
|June 5, 2009
Summary
We explored titanium dioxide (TiO2) photonic crystals (PhCs) for optical devices. Our study provides design guidelines for 2D and 3D TiO2 PhCs, including novel structures and their band gap properties.
Area of Science:
- Materials Science
- Optics
- Nanotechnology
Background:
- Titanium dioxide (TiO2) is a promising material for micro-nano optical devices due to its suitability for visible light applications.
- Photonic crystals (PhCs) offer unique optical properties through their periodic structures.
Purpose of the Study:
- To compute optical band gap maps for 2D and 3D TiO2-based PhC structures.
- To provide design guidelines for TiO2 PhCs, including novel configurations.
- To investigate the band gap characteristics of Yablonovite and reversed Yablonovite structures.
Main Methods:
- Planewave expansion method for computing optical band gap maps.
- Simulation of 2D PhC structures (infinite, air-bridge, and sandwich-type).
- Calculation of 3D Yablonovite and reversed Yablonovite structures.
Main Results:
- Comprehensive optical band gap maps for 2D and 3D TiO2 PhCs were computed.
- A robust and easily fabricated "sandwich-type" 2D PhC was proposed and its optimal thickness investigated.
- The reversed Yablonovite structure was found to exhibit a complete band gap, albeit smaller than the normal Yablonovite.
Conclusions:
- The study provides essential design guidelines for TiO2-based PhCs for optical applications.
- Novel 2D and 3D PhC structures were analyzed, expanding the design possibilities.
- The reversed Yablonovite structure's band gap properties were characterized for the first time, opening new avenues for 3D PhC design.
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