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Phenomenological model analysis for semiconductor optical amplifiers and application to time-domain digital
1Institute of Optical Information, Beijing Jiaotong University, Beijing, China. lzyyh2007@yahoo.com.cn
Optics Letters
|September 17, 2008
Summary
Semiconductor optical amplifiers (SOAs) can be modeled for orthogonal polarization rotation (OPR). A novel digital polarization encoding scheme using photoinduced OPR in SOAs achieves 2.5 Gbits/s over 15 km fiber.
Area of Science:
- Optoelectronics
- Optical Communications
- Semiconductor Devices
Background:
- Semiconductor optical amplifiers (SOAs) are crucial components in optical signal processing.
- Understanding polarization dynamics within SOAs is essential for advanced applications.
- Existing models may not fully capture the complex polarization behavior of SOAs.
Purpose of the Study:
- To model SOAs using a lumped-elements sequence for polarization analysis.
- To identify conditions for achieving valuable orthogonal polarization rotation (OPR).
- To propose and demonstrate a novel digital polarization encoding scheme based on photoinduced OPR.
Main Methods:
- Modeling SOAs as a sequence of a polarizer, retarder, and amplifier.
- Implementing photoinduced OPR using a controlled pump laser.
- Optimizing pump wavelength for effective OPR.
- Developing a time-domain digital polarization encoding scheme.
Main Results:
- SOAs can be accurately represented by a specific lumped-elements model.
- Two necessary conditions for OPR were derived, aiding optical signal processing.
- Optimal pump wavelength for photoinduced OPR identified within a 0.4 nm interval.
- Successful demonstration of a 2.5 Gbits/s polarization encoding scheme over 15 km fiber.
Conclusions:
- The proposed SOA model provides insights for all-optical signal processing.
- Photoinduced OPR is a viable mechanism for optical signal manipulation.
- The developed digital polarization encoding scheme is applicable to optical-power-equalized fiber communication.
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