Analysis Of Semiconductor Optical Amplifiers Research Articles

Bi-Directional Narrow Pulse Modulation and Extinction Ratio Analysis of Semiconductor Optical Amplifier

Bi-Directional Narrow Pulse Modulation and Extinction Ratio Analysis of Semiconductor Optical Amplifier

Simple Rules for Optimizing Asymmetries in SOA-Based Mach–Zehnder Wavelength Converters

In this paper, we present an analysis of semiconductor optical amplifier (SOA)-based differential Mach-Zehnder wavelength converters with a specific focus on optimizing performance through intentional asymmetries in optical power splitting, SOA bias, and interferometer phase bias. By introducing a simple conceptual framework for understanding the amplifier pulse dynamics, two simple yet effective design rules are derived. These design rules are validated using pseudorandom code in a comprehensive computer model, demonstrating the performance penalties that result when attempting optimization using only unequal SOA biasing or phase biasing. This work illustrates that dramatic improvements in extinction and eye margin can be achieved with optimized splitter asymmetries, and have significant implications for improved network performance and converter cascadability.

Dynamic control analysis for semiconductor optical amplifier dynamics in optical network applications

For the first time a practical control analysis of semiconductor optical amplifier (SOA) dynamics has been conducted with implementation design considerations, based on a newly developed SOA electrical Spice model. It can be used for optimal design of SOA driver and control circuits within any existing optical network. In addition, a novel dual-control loop is designed and simulated. The two control loops overcome both fast (transient) and slow (steady-state) phenomena. Simulation results of the controlled SOA dynamics are presented, with an implementation example of an SOA high-speed optical switch driver. For optical switching the SOA driver uses a pre-impulse-step injected current as the switching signal. The developed Spice SOA electrical model is used for the predistortion optimization. The simulation results show that an ultrafast driver and control circuit seems feasible. It is also shown that the SOA can operate as a variable attenuator. A dynamic time constant of ~1–2 nsec is achievable using the predistortion scheme. The design and analysis here show that the SOA technology can be used as the switch-fabric core of a bufferless optical network with switching on packet timescales.

Analysis of semiconductor optical amplifier based double-stage all-optical wavelength converter with improved extinction ratio

We theoretically study the temporal dynamics of a semiconductor optical amplifier (SOA) based double-stage wavelength converter in co-propagative configuration. The impact of the SOA number in the device is analyzed. In this work, we are concerned with the gain recovery time shortening while keeping a low level of noise. We also study the pump and probe power influence on a 10 Gbit/s NRZ sequence output extinction ratio and undertake a systematic study when varying the input extinction ratio.

Modeling and Measurement of Noisy SOA Dynamics for Ultrafast Applications

A complete and effective tool for the analysis of semiconductor optical amplifiers (SOAs) in ultrafast telecommunication applications is presented. This model includes gain dynamics, the current induced gain saturation effect, the current-dependent gain dispersion, and the amplified spontaneous emission. Experimental results concerning both stationary and dynamic conditions confirm the model accuracy and its effectiveness in the design of all-optical signal processing schemes based on SOAs. Finally, we study the characteristic times and the efficiencies of SOA fast dynamics in order to investigate the bandwidth limits of these devices. A numerical evaluation, validated by high-resolution measures makes the SOAs suitable to process optical signals up to 160 Gb/s.