Power Flow in a Large-Core Multimode Fiber under External Perturbation and its Applications

Area of Science:

• Optics and Photonics
• Fiber Optics
• Applied Physics

Background:

• Large core optical multimode fibers offer advantages like high power delivery and easy handling.
• Conventional power flow models do not account for external perturbation effects.

Purpose of the Study:

• To investigate the impact of external perturbations on power flow in large core optical fibers.
• To develop and demonstrate applications based on perturbation effects: a sensor and a beam tuner.

Main Methods:

• Modification of the conventional power flow model to include time-varying perturbations.
• Theoretical analysis, numerical simulations, and experimental validation of the modified model.
• Investigation of fiber vibration sensing and doughnut beam tuning.

Main Results:

• Developed a modified power flow model for analyzing perturbation effects in large core fibers.
• Demonstrated a fiber vibration sensor where sensitivity depends on beam profile and higher-order harmonics.
• Achieved real-time tuning of a doughnut intensity profile using external fiber perturbations.

Conclusions:

• External perturbations offer a viable method for controlling and sensing within large core optical fibers.
• The modified model provides a theoretical basis for understanding and exploiting perturbation effects.
• Results pave the way for novel applications in fiber optic sensing and beam manipulation.