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Enhanced Carbon Dioxide Uptake in Drilled Hollow Core Fibers for Raman Spectroscopy
Brandon Demory1, Jorge Arteaga1,2, Sarah Sahota-Dhillon1
1Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California, USA 94550.
Applied Spectroscopy
|April 15, 2025
Summary
This study demonstrates that laser-drilled access holes significantly reduce gas uptake time in hollow-core fiber (HCF) Raman spectroscopy sensors. Optimizing these holes improves sensor response time by threefold for carbon dioxide (CO2) detection.
Area of Science:
- Spectroscopy
- Optical sensing
- Gas analysis
Background:
- Fiber-based Raman spectroscopy offers enhanced signal detection by maximizing optical field and gas overlap.
- Gas uptake in hollow-core fibers (HCFs) is diffusion-limited at ambient pressure, leading to slow sensor response times.
- Improving HCF gas sensor dynamics is crucial for real-time environmental monitoring applications.
Purpose of the Study:
- To investigate and optimize the gas uptake dynamics in HCFs for Raman spectroscopy.
- To reduce the response time of HCF-based gas sensors, specifically for carbon dioxide (CO2).
- To enhance the practical applicability of fiber-based Raman spectroscopy in gas sensing.
Main Methods:
- Characterized CO2 sensor signal intensity as a function of gas concentration.
- Measured gas uptake time in HCFs varying fiber length.
- Laser drilled access holes into HCFs to facilitate gas diffusion.
- Optimized the configuration and number of access holes along the fiber length.
Main Results:
- Established a relationship between Raman signal intensity and CO2 concentration.
- Quantified the impact of fiber length on gas uptake time.
- Demonstrated a threefold reduction in sensor uptake time through optimized access hole design.
- Achieved significantly faster sensor response compared to undrilled HCFs.
Conclusions:
- Laser-drilled access holes are an effective method to accelerate gas uptake in HCFs.
- Optimized HCF designs with access holes substantially improve sensor response times.
- This technique enhances the feasibility of HCF Raman spectroscopy for rapid gas detection.
Keywords:
Raman spectroscopycarbon dioxide detectiongas sensorhollow core fiberlaser drillingleak monitoringMore Related Videos
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