Related Experiment Video
Updated: Jun 15, 2026
15:47
Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Single-mode GaAs-Al(x)Ga(1-x)As rib waveguide switches
Applied Optics
|March 4, 2010
Summary
Metal-oxide-semiconductor rib waveguides offer low loss and efficient modulation. Researchers demonstrated 90% COBRA switching using a 2x4 matrix, indicating potential for integrated optical circuits.
Area of Science:
- Photonics and optical engineering
- Semiconductor device physics
Background:
- Metal-oxide-semiconductor (MOS) rib waveguides are crucial components in integrated photonics.
- Efficient electrooptic modulation is key for optical signal processing and switching.
Purpose of the Study:
- To demonstrate the performance of MOS rib waveguides for polarization-independent operation.
- To showcase the application of these waveguides in a compact optical switch matrix.
Main Methods:
- Fabrication and characterization of metal-oxide-semiconductor rib waveguides.
- Experimental demonstration of COBRA (Coupled-Waveguide Reconfigurable Array) switching using a 2x4 switch matrix.
- Evaluation of switching efficiency and voltage requirements.
Main Results:
- Achieved low loss for arbitrary polarizations in MOS rib waveguides.
- Demonstrated 90% switching efficiency with an applied voltage of 15 V.
- Successfully implemented a functional 2x4 optical switch matrix.
Conclusions:
- MOS rib waveguides are suitable for polarization-insensitive integrated photonic applications.
- The demonstrated COBRA switching performance highlights their potential for complex optical circuit designs.
- These findings suggest versatile applications in advanced optical communication and computing systems.
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