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Updated: Jul 9, 2026
11:08
Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Cavity-enhanced spectroscopy in optical fibers
Optics Letters
|November 23, 2007
Summary
Fiber Bragg gratings (FBGs) enable high-finesse fiber cavities for enhanced optical sensing. These cavities demonstrate long ring-down times and sensitivity to refractive index changes, advancing fiber optic spectroscopy.
Area of Science:
- Optics and Photonics
- Fiber Optics Technology
- Spectroscopy
Background:
- Cavity-enhanced methods are crucial for high-sensitivity measurements.
- Extending these methods to fiber optics presents unique challenges and opportunities.
- Fiber Bragg gratings (FBGs) offer a promising solution for creating stable fiber-based optical cavities.
Purpose of the Study:
- To fabricate and characterize high-finesse fiber cavities using FBGs.
- To investigate the optical losses and performance of these fiber cavities.
- To demonstrate the potential of fiber cavities for evanescent-wave sensing applications.
Main Methods:
- Fabrication of high-finesse fiber cavities using FBGs in doped and hydrogen-loaded fibers.
- Determination of optical losses via Fabry-Perot transmission spectra and cavity ring-down spectroscopy.
- Integration of an evanescent-wave access block within the fiber cavity for sensing.
Main Results:
- Achieved high-finesse fiber cavities with ring-down times exceeding 2 ms at 1563.6 nm for a 10-m cavity.
- Successfully resolved individual laser pulses within the fiber cavity.
- Demonstrated enhanced sensitivity to external refractive index changes using the evanescent-wave access block.
Conclusions:
- FBGs are effective reflectors for creating high-finesse fiber cavities.
- These fiber cavities exhibit excellent performance, including long ring-down times.
- The developed fiber cavities show significant potential for advanced optical sensing and spectroscopy.
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