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Observation of continuous-wave second-harmonic generation in semiconductor waveguide directional couplers
Optics Express
|June 9, 2009
Summary
Researchers observed continuous-wave second-harmonic generation in waveguide directional couplers using a GaAs/AlGaAs system. This nonlinear frequency conversion method achieved a 1.6%W(-1)cm(-2) efficiency, explained by coupled-mode theory.
Area of Science:
- Photonics and Nonlinear Optics
- Semiconductor Materials Science
Background:
- Second-harmonic generation (SHG) is a key nonlinear optical process for frequency conversion.
- Waveguide structures offer enhanced light-matter interaction for nonlinear phenomena.
Purpose of the Study:
- To demonstrate continuous-wave second-harmonic generation in waveguide directional couplers.
- To investigate the performance and underlying physics of this novel configuration.
Main Methods:
- Fabrication of GaAs/AlGaAS waveguide directional couplers.
- Experimental observation of continuous-wave second-harmonic generation.
- Theoretical analysis using coupled-mode theory.
Main Results:
- Observation of four resonance peaks within a ~15nm spectral range.
- Achieved a maximal conversion efficiency of 1.6%W(-1)cm(-2).
- Experimental results are in good agreement with coupled-mode theory predictions.
Conclusions:
- Continuous-wave second-harmonic generation is successfully demonstrated in waveguide directional couplers.
- The GaAs/AlGaAs system provides a viable platform for efficient nonlinear frequency conversion.
- This configuration offers potential for new applications in nonlinear optics and photonics.
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