Polarization evolution in Brillouin scattering with a partially polarized pump

Area of Science:

• Optical Fiber Sensing
• Nonlinear Optics
• Photonics

Background:

• Polarization sensitivity is a significant challenge in Brillouin scattering-based optical fiber sensing.
• Polarization randomization is used to mitigate this issue, but residual polarization remains.
• A model is needed to understand polarization evolution with partially polarized light.

Purpose of the Study:

• To develop a comprehensive theoretical model for polarization evolution in Brillouin scattering with partially polarized pump and Stokes waves.
• To simulate the impact of residual degree of polarization (DOP) on sensing system performance.

Main Methods:

• Development of a theoretical model based on stochastic differential equations (SDEs).
• Coupled SDEs simultaneously incorporate the polarized components and total powers of pump and Stokes waves.
• Simulation of polarization evolution within the optical fiber.

Main Results:

• The model characterizes beam variation with partially polarized pump and Stokes waves.
• The degree of polarization (DOP) of both pump and Stokes waves influences Brillouin gain stability.
• Simulations demonstrate the necessity of simultaneous DOP reduction for stable Brillouin gain.

Conclusions:

• Residual DOP in partially polarized light significantly impacts Brillouin scattering sensing.
• Simultaneous reduction of pump and Stokes wave DOP is crucial for stable Brillouin gain.
• The developed model provides a tool for performance evaluation and optimization of these sensing systems.