SOA Amplifiers

SOA Gain Saturation – Gaussian Pulses

Optical System - Figure 12 SOA amplified internal loss Gaussian pulse signal

Amplification of ultra-short optical pulses in SOA produces considerable spectral broadening and distortion due to the non-linear phenomenon of self-phase modulation. The physical mechanism behind SPM is gain saturation, which leads to intensity-dependent changes of refractive index in response to variations in carrier density. Signal-gain saturation in SOA is caused by a reduction of the…

SOA Gain Saturation – Comparison with Experimental Results

Optical System - Figure 5 Time and frequency domain of initial and amplified pulses

This lesson applies the results from SOA gain saturation—Gaussian pulses for interpretation of the experimental results on the amplification of Gaussian pulse with SOA obtained in [1]. The aim of [1] was to report the first investigation of the spectral characteristics of pulse amplification in SOA. Parameters of SOA given in the paper are: Saturation…

SOA Gain Saturation – Chirped and Super Gaussian Pulses

Optical System - Figure 1 SOA parameters

This lesson continues to study the effect of gain saturation induced self-phase modulation on the amplification of optical pulses. We will concentrate on the pulses with different shape and initial frequency shift. The chirped Gaussian input pulses are the pulses which are usually produced from directly modulated semiconductor lasers. As in SOA gain saturation—Gaussian pulses,…

SOA Gaussian Pulse – Gain Recovery

Optical System - Figure 1 SOA parameters

In the previous three lessons, we assumed that the input pulse was much shorter than the carrier lifetime. When the pulse width becomes comparable to the carrier lifetime, the saturated gain has time to recover during the pulse. The recovery effect influences the shape and spectrum of the amplified pulse. This lesson studies this influence.…

SOA Pulse Compression

Optical System - Figure 10 Shape and spectra of pulses with 3, 30, and 60 mW peak power

This lesson applies the results from SOA gain saturation—Gaussian pulses to analyze the possibility for compression of weak picosecond pulses. As mentioned in SOA gain saturation—Gaussian pulses, one of the main results of the gain saturation induced self-phase modulation in SOA is the formation of positive chirp of the pulse in the process of amplification.…

SOA as a Wavelength Converter (FWM)

Optical System - Figure 1 Two multiplexed CW signals

This lesson demonstrates the application of traveling wave SOA as a wavelength converter using the four-wave mixing effect. Four-wave mixing (FWM) is a nonlinear effect that takes place when two waves (signal and pump) at different wavelengths are injected into an SOA. A third optical field is generated at the device output, with frequency Wc…

SOA as a Wavelength Converter (XGM)

Optical System - Figure 10 Shape and spectrum of the signal at  = 1540 nm

This lesson demonstrates the application of traveling wave SOA as a wavelength converter using cross-gain saturation effect. The principle use of the cross-gain modulation in SOA is as an intensity-modulated input signal that modulates the gain in the SOA via gain saturation effect. A continuous wave signal at the selected output wavelength is modulated by…

SOA In-Line Amplifier

Optical System - Figure-9-SOA-pulse-patterns

One possible way to upgrade an existing network from previously installed standard optical fibers is to exploit the 1.3 mm optical window, where the step index fibers have a zero-dispersion wavelength using SOA. The advantages of using SOA as in-line single-channel optical amplifiers are: low dispersion of the SMF at this carrier wavelength attractive features…

Wideband SOA Characterization

Optical System - Figure 4 Noise spectra for different input signal powers

The objective of this lesson is to characterize a semiconductor optical amplifier (SOA) through simulations. Initially, we are going to characterize the SOA response to the variation in the input signal power. Figure 1 shows the system layout used in the simulation. We put the power parameter in the CW laser in sweep mode and…

Wavelength Conversion in a Wideband SOA

Optical System - Figure 3 Wavelength converted signal at 1550 nm

The objective of this lesson is to demonstrate the wavelength conversion using the wideband SOA component. Based on the results from the lesson “Wideband SOA Characterization”, we have designed a wavelength converter using the cross-gain modulation method. The system designed is shown in Figure 1. Figure 1: Wavelength converter system layout In the simulation, the…