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Updated: Sep 11, 2025

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Automation of Mode Locking in a Nonlinear Polarization Rotation Fiber Laser through Output Polarization Measurements
Published on: February 28, 2016
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Coupling between orbital-angular-momentum modes in a helically bent ring-core optical fiber.
Optics Express
|August 13, 2025
Summary
Orbital angular momentum (OAM) mode coupling in helical bent fiber waveguides shows direction-dependent behavior. This research aids in designing advanced OAM-based optical devices.
Area of Science:
- Optics and Photonics
- Waveguide Theory
- Fiber Optics
Background:
- Orbital angular momentum (OAM) enables novel optical functionalities.
- Ring-core fiber waveguides support OAM modes.
- Helical bending introduces unique waveguide characteristics.
Purpose of the Study:
- Investigate OAM mode coupling in helically bent ring-core fiber.
- Analyze the impact of bending parameters on OAM coupling.
- Understand directional asymmetry in OAM propagation.
Main Methods:
- Analytical modeling of OAM mode coupling.
- Numerical simulations of light propagation in bent fibers.
- Parametric study of bending radius, frequency, and helicity.
Main Results:
- Identified significant coupling between different OAM modes.
- Demonstrated directional asymmetry in coupling behavior.
- Quantified the influence of bending parameters on coupling strength.
Conclusions:
- Helical bending induces asymmetric OAM mode coupling in ring-core fibers.
- Findings are crucial for optimizing OAM-based optical device performance.
- Results provide a basis for future OAM communication and sensing technologies.
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