Information on the simulation method and background is in this presentation. The program is based on the work presented therein. The equations for the optical amplification are derived from work by Tang and Shore adapted for a logarithmic gain carrier relationship. Spontaneous emission (SE) is also included. It is modeled by adding SE power (white noise) to the other optical power in the amplifier segments as a vector.
The derivations of the amplifier equations used are in this MathCAD sheet (pdf file) and this MathCAD sheet (pdf file) for the passive waveguides with TPA and Kerr effect. Included are also the definitions of the constants used in the code and a sanity check on their values.
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Encyclopedia of Laser Physics and Technology
This encyclopedia explains basic terms and principles of laser physics and technology, with additional content from other topics such as general optics, nonlinear optics, fiber optics, quantum optics, and optical communications.