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Radial polarization induced surface plasmon virtual probe for two-photon fluorescence microscopy
1School of Electrical & Electronic Engineering, Nanyang Technological University, Singapore, Singapore.
Optics Letters
|April 3, 2009
Summary
A sharp surface plasmon peak acts as a virtual probe for microscopy. Radially polarized light enables nonlinear process studies on metal surfaces.
Area of Science:
- Optics and Photonics
- Materials Science
Background:
- Surface plasmons are coherent electron oscillations on metal surfaces.
- Exciting surface plasmons requires specific polarization conditions.
Purpose of the Study:
- To introduce a novel "virtual probe" for surface plasmon microscopy.
- To investigate the use of femtosecond radially polarized beams for surface plasmon excitation.
Main Methods:
- Excitation of surface plasmons using a focused femtosecond radially polarized beam.
- Formation of a standing wave pattern with a sharp peak.
- Utilizing the probe for nonlinear process studies.
Main Results:
- A sharp peak in the surface plasmon standing wave pattern was achieved.
- Radially polarized light effectively provided the necessary TM polarization for coupling.
- The femtosecond pulse nature enabled the study of nonlinear optical processes.
Conclusions:
- The "virtual probe" generated by surface plasmons offers a new tool for high-resolution microscopy.
- Femtosecond radially polarized beams are suitable for advanced surface plasmon studies, including nonlinear phenomena.
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