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Updated: Jul 6, 2026
09:39
In-situ Tapering of Chalcogenide Fiber for Mid-infrared Supercontinuum Generation
Published on: May 27, 2013
Modal coupling in surface-corrugated long-period-grating fiber tapers.
W Ding1, S R Andrews, S A Maier
1Centre for Photonic Materials, Department of Physics, University of Bath, Claverton Down, Bath, UK. pypwd@bath.ac.uk
Optics Letters
|April 3, 2008
Summary
A new surface-corrugated fiber taper was fabricated. A mode-projection model accurately explains its modal behavior, unlike traditional coupled-mode theory.
Area of Science:
- Optoelectronics
- Fiber Optics
- Nanofabrication
Background:
- Long-period gratings (LPGs) are crucial optical fiber components.
- Understanding modal behavior in corrugated gratings is essential for device design.
- Existing theories like coupled-mode theory (CMT) may not fully capture complex grating interactions.
Purpose of the Study:
- To fabricate and characterize a surface-corrugated long-period grating fiber taper.
- To investigate the modal behavior of this novel fiber device.
- To evaluate the applicability of existing theories and propose a more suitable model.
Main Methods:
- Fabrication using contact optical lithography and wet etching.
- Characterization of transmission spectra.
- Comparison of experimental data with theoretical models (CMT and mode-projection).
Main Results:
- Successful fabrication of a surface-corrugated long-period grating fiber taper preserving cylindrical symmetry.
- Measured transmission spectra deviate significantly from predictions based on coupled-mode theory.
- A mode-projection model accurately explains the observed modal propagation and coupling phenomena.
Conclusions:
- Coupled-mode theory is insufficient for analyzing surface-corrugated long-period gratings.
- The mode-projection model provides a superior framework for understanding and predicting the behavior of these devices.
- This work offers improved theoretical tools for designing advanced fiber optic components.
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