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Writing Bragg Gratings in Multicore Fibers
Published on: April 20, 2016
Light coupling between two parallel CO2-laser written long-period fiber gratings
Yunqi Liu1, Kin Seng Chiang, Yun Jiang Rao
1Department of Electronic Engineering, City University of Hong Kong, Hong Kong, China. eeyqliu@cityu.edu.hk
Optics Express
|June 25, 2009
Summary
We show how carbon dioxide (CO2)-laser written long-period fiber gratings enable efficient light coupling. Boron-doped fibers offer orientation-independent coupling, achieving 86% efficiency for broadband all-fiber couplers.
Area of Science:
- Photonics and Optical Engineering
- Materials Science
- Fiber Optics
Background:
- Long-period fiber gratings (LPFGs) are crucial optical components.
- CO2 laser fabrication offers precise control over grating parameters.
- Understanding inter-grating coupling is key for advanced fiber devices.
Purpose of the Study:
- To experimentally investigate light coupling effects between two parallel CO2-laser written LPFGs.
- To analyze the influence of fiber type and orientation on coupling efficiency.
- To demonstrate the potential for creating efficient all-fiber couplers.
Main Methods:
- Fabrication of parallel LPFGs using a CO2 laser.
- Experimental measurement of light coupling efficiency between gratings.
- Varying grating parameters such as fiber type, orientation, surrounding refractive index, and offset distance.
Main Results:
- Coupling efficiency in standard single-mode fibers is highly dependent on fiber orientation.
- Coupling efficiency in boron-doped fibers is independent of fiber orientation.
- A peak coupling efficiency of approximately 86% was achieved in boron-doped fibers.
- Optimized surrounding refractive index and offset distance enhance coupling.
Conclusions:
- CO2 laser written LPFGs facilitate efficient inter-grating light coupling.
- Boron-doped fibers provide orientation-independent coupling, simplifying device fabrication.
- These findings pave the way for developing high-performance, broadband all-fiber couplers.
