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Polarization, scattering, and coherent effects in semiconductor rib waveguide bends.
Optics Letters
|September 12, 2009
Summary
Circular bend attenuation in GaAs/AlGaAs rib waveguides shows strong polarization dependence. Coherent coupling oscillations were weaker than predicted, impacting optical device design.
Area of Science:
- Optoelectronics and Photonics
- Semiconductor Materials Science
Background:
- Gallium Arsenide (GaAs)/Aluminum Gallium Arsenide (AlGaAs) heterostructures are fundamental in optoelectronic devices.
- Rib waveguides are crucial for integrated photonic circuits, but bend losses can limit performance.
Purpose of the Study:
- To investigate the detailed behavior of circular bend attenuation in GaAs/AlGaAs rib waveguides.
- To compare experimental findings with theoretical predictions, specifically beam-propagation calculations.
Main Methods:
- Experimental characterization of bend loss in GaAs/AlGaAs rib waveguides.
- Theoretical modeling and simulation using beam-propagation methods.
Main Results:
- Observed strong polarization dependence of bend loss in the waveguides.
- Measured coherent coupling oscillations significantly weaker than theoretical predictions.
Conclusions:
- Polarization effects are critical for understanding bend attenuation in these waveguides.
- Current beam-propagation models may require refinement for accurate prediction of coupling oscillations in such structures.
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