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Bidirectional modeling of reflection-induced gain and noise dynamics in semiconductor optical amplifiers
Optics Express
|December 19, 2025
Summary
Reflections in semiconductor optical amplifiers (SOAs) cause significant noise. A new bidirectional model shows how these reflections, amplified by environmental factors, degrade performance, necessitating careful system design.
Area of Science:
- Photonics
- Semiconductor device physics
- Optical engineering
Background:
- Reflections in semiconductor optical amplifiers (SOAs) degrade performance in silicon photonics.
- Existing models fail to capture noise from bidirectional coupling.
Purpose of the Study:
- To develop a self-consistent bidirectional model for SOAs.
- To analyze the impact of reflections on noise and gain dynamics.
Main Methods:
- Developed a bidirectional propagation model.
- Included nonlinear gain saturation and phase-sensitive interference.
- Investigated the impact of external noise sources.
Main Results:
- Bidirectional coupling significantly increases excess intensity noise.
- Noise levels can approach the amplified spontaneous emission (ASE) floor.
- Modest reflections combined with vibrations/drift amplify noise.
Conclusions:
- A bidirectional model is crucial for understanding SOA noise.
- Reflection-induced noise must be considered in heterogeneously integrated III-V/Si systems.
- The model aids in optimizing active photonic devices.
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