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Intrinsic polarity inversion in III-nitride waveguides for efficient nonlinear interactions
Optics Express
|September 15, 2023
Summary
We demonstrate a novel composite waveguide using gallium nitride (GaN) and aluminum nitride (AlN) layers for enhanced nonlinear photonics. This design achieves a significant 4%W⁻¹cm⁻² conversion efficiency for second harmonic generation, surpassing previous III-nitride waveguide results.
Area of Science:
- Materials Science
- Photonics
- Nonlinear Optics
Background:
- III-nitrides, such as gallium nitride (GaN) and aluminum nitride (AlN), are promising materials for nonlinear photonics.
- Existing nonlinear optical devices face limitations due to mode overlap issues in waveguide configurations.
Purpose of the Study:
- To explore a novel composite waveguide design using GaN and AlN layers with inverted polarity.
- To enhance the efficiency of nonlinear optical interactions by improving mode overlap.
Main Methods:
- Theoretical modeling of composite waveguides with inverted polarity.
- Experimental fabrication and characterization of GaN/AlN ridge waveguides.
- Measurement of second harmonic generation (SHG) conversion efficiency.
Main Results:
- The composite waveguide design with inverted polarity effectively addresses mode overlap limitations.
- Experimental demonstration of SHG with a conversion efficiency of 4%W⁻¹cm⁻².
- Achieved efficiency is an order of magnitude higher than previous III-nitride waveguides.
Conclusions:
- Composite III-nitride waveguides with inverted polarity offer a significant advancement for nonlinear photonics.
- The demonstrated efficiency highlights the potential for further improvements by reducing propagation losses.
- This approach paves the way for highly efficient nonlinear optical devices based on III-nitrides.
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