Author: Xiaojun (James) Chen from Inline Photonics Inc. Email: [email protected]

This open-source Python program was developed for the book "Polarization Measurement and Control in Optical Fiber Communication and Sensor Systems." By X. Steve Yao and Xiaojun(James) Chen. The package includes the following:

1. PolaTrace library named polatrace.py is a library to display and emulates the optical polarization phenomenon in fiber.

2. Application examples of the PolarTrace library:

Example 1: PolarizationEllipse.py. It displays polarization ellispe according to the inputs of amplitudes of Ex and Ey, and the phase difference between Ey and Ex:

Example 2: JV-Ellipse-Stokes.py. It represents the polarization of a given optical electric field in polarization ellispe, and a Stokes vector on Poincare sphere.

Example 3: Polarizaion elements.py. It displays the relationship between the input and output polarization state after light passes a polarization element, for example, waveplate, rotator, and partial polarizer. This program also shows the trace output polarization on the Poincare sphere when retardation or optical axis orientation is changed. This program can be used as a conversation between the Jones vector and the Stokes parameters of monochromatic light.

Example 4: Spun fiber.py. This program calculates and displays the polarization states evaluation along a spun fiber. The spun fiber is modeled by a continuously rotated linear polarization maintaining fiber. One can change the input polarization state, intrinsic linear birefringence, and rotating rate to see how these parameters influence polarization evaluation along the spun fiber.

Example 5: PMD simulation.py. This program calculates the polarization mode dispersion(PMD of a fiber consisting of six DGD segments. The curves of PMD vs. wavelength are displayed in the left graphs. The corresponding polarization principle state (PSP) and SOP evaluation vs. wavelength are shown on the Poincare sphere. One can change the DGD values of each fiber segment and their relative orientation angles to research how these parameters change the overall PMD of the fiber.