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Writing Bragg Gratings in Multicore Fibers
Published on: April 20, 2016
Optical coupling between a long-period fiber grating and a parallel tilted fiber Bragg grating
Yunqi Liu1, Qing Liu, Kin Seng Chiang
1Key Laboratory of Specialty Fiber Optics and Optical Access Networks, School of Communication and Information Engineering, Shanghai University, 149 Yanchang Road, Shanghai 200072, China.
Optics Letters
|June 3, 2009
Summary
We demonstrated efficient contradirectional optical coupling between two parallel fibers using gratings. This method achieves high coupling efficiency for developing narrow-band all-fiber optical components.
Area of Science:
- Photonics and Optical Engineering
- Fiber Optics
- Grating-based Devices
Background:
- Optical fiber components are crucial for telecommunications and sensing.
- Long-period fiber gratings (LPGs) and tilted fiber Bragg gratings (TFGbs) are key photonic structures.
- Efficient coupling between optical fibers is essential for device miniaturization and performance.
Purpose of the Study:
- To experimentally demonstrate contradirectional optical coupling between two parallel fibers.
- To investigate coupling between cladding modes of the same order in LPGs and TFGbs.
- To optimize coupling conditions for high efficiency and narrow bandwidth.
Main Methods:
- Utilizing two parallel optical fibers, one with an LPG and the other with a TFG.
- Exploiting the overlapped resonance bands of the LPG and TFG for cladding mode coupling.
- Optimizing fiber alignment and grating parameters to achieve maximal coupling efficiency.
Main Results:
- Achieved a peak coupling efficiency of approximately 80% at 1,534 nm.
- Demonstrated a narrow 3 dB bandwidth of approximately 0.12 nm.
- Obtained a side-mode suppression ratio of approximately 16 dB, independent of the input fiber.
Conclusions:
- Contradirectional coupling between LPG and TFG is experimentally verified.
- The demonstrated coupler exhibits high efficiency and narrow bandwidth.
- This configuration shows potential for developing advanced narrow-band all-fiber optical components.
