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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Resonant coupling in trenched bend-insensitive optical fiber.
Guobin Ren1, Zhen Lin, Siwen Zheng
1Key Laboratory of All Optical Network & Advanced Telecommunication Network of EMC, Beijing Jiaotong University, Beijing 100044, China. gbren@bjtu.edu.cn
Optics Letters
|March 5, 2013
Summary
We discovered resonant coupling in bend-insensitive fiber (BIF). Core-trench distance is key for BIF design, as coupling limits bending loss, even in double-trenched designs.
Area of Science:
- Optical Fiber Technology
- Photonics
- Materials Science
Background:
- Bend-insensitive fibers (BIFs) are crucial for compact optical systems.
- Understanding loss mechanisms in BIFs under bending is essential for performance optimization.
- Trenched BIF designs aim to mitigate bending losses.
Purpose of the Study:
- To investigate the resonant coupling mechanism in trenched bend-insensitive fibers (BIFs).
- To identify key design parameters influencing resonant coupling and bending loss.
- To evaluate the impact of resonant coupling on BIF performance, including double-trenched designs.
Main Methods:
- Theoretical analysis of resonant coupling in trenched BIFs.
- Numerical simulations to model light propagation and loss.
- Parametric study focusing on core-trench distance and other trench parameters.
Main Results:
- Resonant coupling is an intrinsic characteristic of trenched BIFs.
- Core-trench distance is the predominant parameter for optimizing BIF design.
- Resonant coupling between the fiber core and innermost cladding limits ultimate bending loss in BIFs under tight bends.
- Resonant coupling also occurs in double-trenched BIFs, impairing their bending performance.
Conclusions:
- Resonant coupling is a fundamental factor limiting the performance of trenched BIFs.
- Optimized BIF design requires careful control of the core-trench distance to manage resonant coupling.
- The findings provide insights for developing next-generation BIFs with improved bending resilience.
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