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Updated: Jun 19, 2026
07:39
Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
Two-photon-excited fluorescence enhanced by a surface plasmon.
Optics Letters
|November 3, 2009
Summary
Surface-plasmon resonance significantly boosts multiphoton excitation fluorescence intensity by 90x. This technique enhances electric fields for brighter fluorescence signals, offering a powerful tool for optical measurements.
Area of Science:
- Optics and Photonics
- Biophysics
- Materials Science
Background:
- Multiphoton excitation microscopy offers advantages in deep tissue imaging.
- Enhancing fluorescence signals is crucial for improving imaging sensitivity and resolution.
- Surface-plasmon resonance (SPR) is known for its ability to concentrate electromagnetic fields.
Purpose of the Study:
- To demonstrate a novel technique for intensifying fluorescence via surface-plasmon resonance.
- To quantify the fluorescence enhancement achieved using SPR compared to traditional methods.
- To investigate the wavelength-dependent performance of SPR for fluorescence enhancement.
Main Methods:
- Utilizing surface-plasmon resonance to enhance the electric field of excitation laser light.
- Employing multiphoton excitation for fluorescence generation.
- Comparing fluorescence intensity from SPR-enhanced excitation with total internal reflection fluorescence (TIRF).
- Analyzing the effect of excitation wavelength on SPR enhancement efficacy.
Main Results:
- Achieved a 90-fold increase in experimentally observed fluorescence intensity compared to TIRF.
- Demonstrated significant intensification of fluorescence through SPR-mediated electric field enhancement.
- Characterized the SPR enhancement as a function of excitation wavelength, providing performance data.
Conclusions:
- Surface-plasmon resonance is a highly effective method for intensifying fluorescence in multiphoton excitation.
- The SPR technique offers a substantial improvement in signal gain for fluorescence-based imaging and sensing.
- This approach has potential applications in various fields requiring sensitive optical detection.
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