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Temperature-Controlled Assembly and Characterization of a Droplet Interface Bilayer
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Bandwidth control of a Ti:PPLN Solc filter by a temperature-gradient-control technique
Yeung Lak Lee1, Young-Chul Noh, Chul-Sik Kee
11Nonlinear Optics Laboratory, Advanced Photonics Research Institute, GIST, 1 Oryong-dong, Buk-gu, Gwangju 500-712, Republic of Korea.
Optics Express
|September 6, 2008
Summary
We controlled the filtering bandwidth of a Ti-diffused periodically poled lithium niobate (Ti:PPLN) Solc filter using a temperature gradient. This technique increased the bandwidth from 0.2 nm to 2.8 nm in a 78-mm waveguide.
Area of Science:
- Photonics and optical engineering
- Materials science
Background:
- Periodic structures in lithium niobate are crucial for nonlinear optical devices.
- Ti:PPLN waveguides offer unique properties for integrated optics.
- Solc filters are widely used for wavelength selection.
Purpose of the Study:
- To demonstrate bandwidth control of a Ti:PPLN Solc filter.
- To investigate the effect of temperature gradients on filter bandwidth.
- To analyze experimental results using theoretical calculations.
Main Methods:
- Fabrication of a Ti-diffused periodically poled lithium niobate (Ti:PPLN) waveguide.
- Implementation of a temperature-gradient-control technique.
- Analysis using codirectional coupled mode equations.
Main Results:
- Achieved a filtering bandwidth of 2.8 nm using the temperature-gradient-control technique.
- Demonstrated a significant increase from the original 0.2 nm bandwidth at uniform temperature.
- Validated experimental findings with theoretical calculations.
Conclusions:
- Temperature-gradient control is an effective method for bandwidth tuning in Ti:PPLN Solc filters.
- The developed technique offers a simple yet powerful way to enhance filter performance.
- Theoretical analysis supports the experimental observations, providing a deeper understanding of the underlying physics.
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