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Polarization effects in tapered dielectric waveguides
Optics Express
|May 26, 2009
Summary
The 3D finite-difference time-domain method analyzes polarization in tapered optical waveguides. It compares reflected and output powers for slab and rectangular waveguides, detailing TE and TM mode behavior.
Area of Science:
- Optics and Photonics
- Computational Electromagnetics
Background:
- Optical waveguides are crucial for light manipulation.
- Understanding polarization effects in tapered structures is essential for device design.
Purpose of the Study:
- To analyze polarization effects in linearly tapered optical waveguides using the 3D finite-difference time-domain method.
- To compare power characteristics of different waveguide geometries and taper types.
Main Methods:
- Utilized the 3D finite-difference time-domain (FDTD) method.
- Analyzed slab waveguides with lateral tapers.
- Investigated rectangular waveguides with lateral and vertical tapers.
Main Results:
- Determined and compared back reflected and output powers for guided modes in slab waveguides.
- Computed and compared output powers of TE and TM modes concerning taper length in rectangular waveguides.
Conclusions:
- The 3D FDTD method effectively models polarization effects in tapered waveguides.
- Comparative analysis provides insights into mode behavior and power distribution in different taper configurations.
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