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Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Dual-negative refraction in photonic crystals with hexagonal lattices
1Department of Materials Science and Engineering, Tsinghua University, Beijing, 100084, China. gydong@tsinghua.edu.cn
Optics Express
|July 1, 2011
Summary
Researchers achieved dual-negative refraction in a 2D triangular photonic crystal, enabling wave-front division and double focusing imaging. This photonic crystal effect offers potential for advanced optical devices and fundamental physics insights.
Area of Science:
- Optics and Photonics
- Materials Science
- Condensed Matter Physics
Background:
- Photonic crystals (PhCs) offer unique light manipulation properties.
- Negative refraction phenomena are crucial for advanced optical applications.
- Holographic lithography enables complex PhC structures.
Purpose of the Study:
- To demonstrate and investigate dual-negative refraction in a 2D triangular photonic crystal.
- To explore the tunability of this effect via incident parameters and PhC properties.
- To showcase potential applications in wave-front division, optical interference, and imaging.
Main Methods:
- Fabrication of a 2D triangular photonic crystal using holographic lithography.
- Theoretical analysis and simulation of wave propagation within the PhC.
- Investigation of the photonic band structure and its relation to negative refraction.
Main Results:
- Observed dual-negative refraction of a single incident plane wave into two negative refracted waves.
- Demonstrated tunability of the negative refraction effect by adjusting incident angle, frequency, and filling ratio.
- Achieved double focusing imaging using a PhC slab based on the dual-negative refraction.
Conclusions:
- The dual-negative refraction effect in 2D triangular PhCs is achievable and controllable.
- This phenomenon has significant implications for optical holography, wave-front division, and imaging.
- The findings hold promise for fundamental physics research and the development of novel optical devices.
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