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Updated: Dec 5, 2025

Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
Layer analysis of axial spatial distribution of surface plasmon resonance sensing
Yi Sun1, Haoyuan Cai2, Xiaoping Wang2
1Ocean College, Zhejiang University, Zhoushan, Zhejiang, 316021, China; Key Laboratory of Ocean Observation-Imaging Testbed of Zhejiang Province, Zhejiang University, Zhoushan, 316021, China; Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.
Abstract:
The spatial distribution detection and characterization of multi-adsorption layers, biomembranes, and cells are important techniques to study biomolecular properties and mechanisms. Using the surface plasmon resonance (SPR) technology, we investigated the spatial characteristics, penetration mechanism, and detection depth of the interaction between evanescent waves and a complex medium. In addition, parameters correlated with the axial spatial distribution were analyzed. We found that the spatial refractive-index distribution of an axial layered model has a unique correlation with the following three characteristic parameters: resonance angle at different wavelengths, first-derivative extreme-point of the angular spectrum, and effective refractive index. A new layer-analysis, based on wavelength-scanning angle interrogation (WSAI), was introduced to enable refractive-index measurements in an axial spatial medium. This new method extends the detection capabilities of SPR sensors and provides a more accurate analysis method for interaction events within an evanescent field.

