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Updated: Jun 19, 2026
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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Core-resonance capillary-fiber whispering-gallery-mode laser
Optics Letters
|October 3, 2009
Summary
Researchers observed laser emission from a dye-doped solvent flowing in a silica fiber. This cylindrical whispering-gallery-mode laser relies on total internal reflection at the liquid-silica interface for feedback.
Area of Science:
- Optics and Photonics
- Materials Science
Background:
- Whispering-gallery mode (WGM) lasers are typically spherical.
- Previous WGM lasers lacked internal refractive index discontinuities.
Purpose of the Study:
- To demonstrate laser emission from a cylindrical WGM laser.
- To investigate the role of refractive index discontinuity in WGM laser operation.
Main Methods:
- Observation of laser emission from a dye-doped solvent in a silica capillary fiber.
- Boundary-value computations to analyze feedback mechanisms.
Main Results:
- Laser emission observed at wavelengths corresponding to WGM.
- Feedback mechanism identified as total internal reflection at the liquid-silica interface.
- Lasing was dependent on the solvent's refractive index being higher than silica's.
Conclusions:
- A novel cylindrical WGM laser design utilizing a refractive index discontinuity is presented.
- Total internal reflection at the liquid-silica interface is crucial for lasing.
- The refractive index of the solvent must exceed that of the silica for laser operation.
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