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Concept for phase-to-intensity conversion in SOAs by facet reflections.
1DTU Fotonik, Department of Photonics Engineering, Technical University of Denmark, Building 343, DK-2800 Kongens Lyngby, Denmark. sblj@fotonik.dtu.dk
Optics Letters
|March 3, 2010
Summary
Minute reflections in semiconductor optical amplifiers (SOAs) enable all-optical conversion from phase-modulated to intensity-modulated signals. This interference effect, amplified by SOA gain, allows for optical modulation format conversion.
Area of Science:
- Optoelectronics
- Photonics
- Semiconductor Devices
Background:
- Optical communication systems rely on efficient modulation formats.
- Converting between phase-modulated and intensity-modulated signals is crucial for signal processing.
- Semiconductor optical amplifiers (SOAs) are key components in optical networks.
Purpose of the Study:
- To theoretically demonstrate all-optical conversion from phase-modulated to intensity-modulated signals using SOAs.
- To investigate the role of reflections in enabling this conversion process.
- To explore the potential application of this phenomenon for optical modulation format interconversion.
Main Methods:
- Theoretical demonstration of all-optical conversion.
- Large-signal and small-signal calculations within SOAs.
- Analysis of interference effects caused by signal reflections.
Main Results:
- Significant phase-to-intensity conversion responses were observed.
- Minute reflections at SOA end mirrors were found to be critical for conversion.
- Amplified interference due to reflected phase-modulated signals leads to intensity fluctuations.
Conclusions:
- All-optical conversion from phase to intensity modulation is feasible in SOAs.
- Signal reflections within SOAs can be harnessed for modulation format conversion.
- This effect offers a novel method for manipulating optical modulation formats.
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