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Updated: Jan 25, 2026

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Nanostructured Ag-zeolite Composites as Luminescence-based Humidity Sensors
Published on: November 15, 2016
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Au nanorod-coupled microfiber optical humidity sensors
Optics Express
|May 5, 2019
Summary
This study presents a novel optical sensor for measuring relative humidity (RH) using gold nanorods and microfiber. The sensor achieves high sensitivity and offers potential for distributed, high-resolution humidity detection.
Area of Science:
- Nanophotonics
- Optical Sensing
- Materials Science
Background:
- Whispering gallery mode resonators are sensitive to environmental changes.
- Plasmon resonance in nanostructures offers unique optical properties.
Purpose of the Study:
- To develop a high-sensitivity optical sensor for relative humidity (RH).
- To explore the integration of plasmonic nanorods with microfiber resonators for enhanced sensing capabilities.
- To demonstrate a position-dependent sensing mechanism for distributed measurements.
Main Methods:
- Coupling single gold nanorods to polyacrylamide microfiber whispering gallery modes.
- Utilizing the plasmon resonance peak shift for RH detection.
- Integrating multiple gold nanorods along the microfiber for spatial resolution.
Main Results:
- Achieved a high sensitivity of 0.51 nm/% RH with a 2 μm cavity size.
- Demonstrated a position-dependent microfiber optical humidity sensor.
- Attained a spatial resolution of 1.5 mm, with potential for micrometer-level resolution.
Conclusions:
- The developed sensor offers high sensitivity and selectivity for RH detection.
- The integration of plasmonic nanorods with microfiber cavities enables advanced optical sensing.
- This technology paves the way for high-resolution distributed optical humidity sensors.
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