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Design of electromagnetic refractor and phase transformer using coordinate transformation theory
Lan Lin1, Wei Wang, Jianhua Cui
1State Key Laboratory of Optical Technologies for Microfabrication, Institute of Optics and Electronics,Chinese Academy of Sciences, Chengdu 610209, China.
Optics Express
|June 12, 2008
Summary
We developed novel electromagnetic devices using coordinate transformation. These devices control electromagnetic energy propagation, offering low reflection and wavefront manipulation for advanced optics.
Area of Science:
- Electromagnetism
- Metamaterials
- Wave Optics
Background:
- Conventional dielectric refractors follow Snell's law, leading to reflections.
- Controlling electromagnetic energy propagation is crucial for optical devices.
- Maxwell's equations govern electromagnetic field behavior.
Purpose of the Study:
- To design an electromagnetic refractor and phase transformer.
- To modulate the propagation direction of electromagnetic energy.
- To achieve low reflection and wavefront transformation.
Main Methods:
- Form-invariant coordinate transformation of Maxwell's equations.
- Designing devices based on transformed equations.
- Two-dimensional finite-element simulations for validation.
Main Results:
- Developed an electromagnetic refractor with impedance matching, minimizing reflection.
- Achieved desired modulation of electromagnetic energy propagation direction.
- Demonstrated wavefront transformation from cylindrical to plane using a slab structure.
- Simulations confirmed theoretical predictions.
Conclusions:
- The designed electromagnetic refractor and phase transformer offer novel functionalities.
- These devices overcome limitations of conventional refractors by minimizing reflection.
- The approach enables precise control over electromagnetic wave propagation and wavefront shaping.
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