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Updated: Jul 8, 2026
15:06
Measurement of Scattering Nonlinearities from a Single Plasmonic Nanoparticle
Published on: January 3, 2016
Linear and non-linear spectroscopy of microparticles: basic principles, new techniques and promising applications
1Yale University, Department of Applied Physics, P.O. Box 208284, New Haven, CT 06520-8284, USA. Richard.Chang@yale.edu
Faraday Discussions
|January 25, 2008
Summary
This study explores whispering gallery modes (WGMs) in micro-resonators for spectroscopy. New techniques enable precise measurements for applications like bioaerosol identification.
Area of Science:
- Optics and Photonics
- Materials Science
- Spectroscopy
Background:
- Dielectric micro-particles function as micro-cavities or micro-resonators.
- Whispering gallery modes (WGMs) are fundamental to understanding light interaction with these micro-structures.
- WGMs have relevance in semiconductor lasers, nonlinear optics, and fiber optics.
Purpose of the Study:
- To present the basic principles of WGMs and their relation to electromagnetic theory.
- To introduce novel techniques for measuring micro-particle properties and interfacial biochemical reactions.
- To explore applications in bioaerosol characterization and identification.
Main Methods:
- Simplified 2-D model of light illumination perpendicular to a fiber axis.
- Graphical plotting of internal and near-field WGM distribution.
- Development of techniques for measuring nanometer changes in fiber diameter, micro-particle morphology via elastic scattering, and biochemical reactions at liquid-sphere interfaces.
Main Results:
- Demonstration of WGM spatial and spectral distributions.
- Successful measurement of nanometer-scale fiber diameter changes.
- Preliminary results for bioaerosol characterization using elastic scattering and fluorescence spectroscopy.
Conclusions:
- WGMs in dielectric micro-resonators offer significant potential for advanced optical sensing.
- Novel measurement techniques provide precise characterization of micro-particles and their interfaces.
- The study highlights promising applications in ambient aerosol analysis and identification.
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