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Controllability of group-velocity dispersion in semiconductor coupled-waveguide structures
Applied Optics
|March 20, 2008
Summary
Group-velocity dispersion (GVD) in InGaAsP/InP coupled waveguides is controllable by adjusting the spacing between waveguides. Increasing spacing enhances peak GVD but narrows spectral bandwidth, matching theoretical predictions.
Area of Science:
- Optoelectronics
- Semiconductor physics
- Waveguide optics
Background:
- Supermodes in semiconductor coupled-waveguide structures exhibit unique optical properties.
- Group-velocity dispersion (GVD) is a critical parameter affecting pulse propagation in optical waveguides.
Purpose of the Study:
- To experimentally demonstrate the controllability of GVD in InGaAsP/InP coupled-waveguide structures.
- To investigate the effect of waveguide spacing on GVD characteristics.
Main Methods:
- Fabrication of InGaAsP/InP coupled-waveguide structures with varying inter-waveguide spacing.
- Experimental measurement of GVD using pulse broadening and pulse compression techniques.
- Comparison of experimental results with theoretical predictions.
Main Results:
- Controllability of GVD was achieved by altering the spacing between coupled waveguides.
- Increasing waveguide spacing led to higher peak GVD values.
- A narrowing of the spectral bandwidth of GVD was observed as spacing increased.
Conclusions:
- The study successfully demonstrated tunable GVD in semiconductor coupled waveguides.
- Experimental findings align with theoretical predictions, validating the proposed control mechanism.
- This work offers potential for advanced optical signal processing applications.
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