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Updated: Jun 16, 2026
11:08
Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
Summary
Low-loss optical waveguides show significant OH absorption bands at 725, 875, and 950 nm. These absorptions, critical for optical communications, are detectable in waveguides but not bulk glass.
Area of Science:
- Materials Science
- Optical Engineering
- Photonics
Background:
- Experimental single-mode glass optical waveguides achieve 20-dB/km attenuation, driving interest in optical communications.
- The 600-1060 nm wavelength range is crucial for optical communication applications.
Purpose of the Study:
- To independently measure attenuation in low-loss waveguides and bulk glass.
- To identify the sources of attenuation in the 600-1060 nm spectrum.
Main Methods:
- Attenuation measurements were performed on waveguides and bulk cladding glass.
- Laser and scanning-prism monochromator sources were utilized for spectral analysis.
- Measurements spanned the wavelength range from 600 nm to 1060 nm.
Main Results:
- Three distinct absorption bands were identified in the waveguides at 725 nm, 875 nm, and 950 nm.
- These absorption bands were attributed to hydroxyl (OH) presence within the glass material.
- Absorptions, negligible in bulk glass, were significant and measurable within the waveguides.
Conclusions:
- Hydroxyl (OH) groups are a primary source of attenuation in these optical waveguides.
- The waveguide structure amplifies the impact of OH absorption compared to bulk glass.
- Understanding these OH absorptions is vital for optimizing optical waveguides for communication.
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