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Updated: May 26, 2025
07:39
Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
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Stimulated emission does not radiate in a pure dipole pattern.
Andrew E S Barentine1, W E Moerner1,2
1Department of Chemistry, Stanford University, Stanford, California 94305, USA.
Optica
|February 24, 2025
Summary
Stimulated emission (StE) imaging shows that a molecule's emission direction depends on the driving field, not a simple dipole pattern. This finding is crucial for developing advanced microscopy and optical cooling technologies.
Area of Science:
- Optics
- Spectroscopy
- Microscopy
Background:
- Stimulated emission (StE) offers advantages in speed, coherence, and resolution over fluorescence imaging.
- The radiation pattern and directionality of StE from single molecules are not fully understood.
- Previous StE imaging primarily used transmission detection methods.
Purpose of the Study:
- To investigate the radiation pattern and directionality of stimulated emission (StE).
- To clarify the fundamental characteristics of StE for improved microscope design and applications.
- To determine if StE emission follows a classical dipole pattern or is influenced by the driving field.
Main Methods:
- Introduced the StE driving field (probe) at an angle.
- Utilized total internal reflection to eliminate incident probe light and reflections in detection.
- Employed a non-collinear detection configuration to simultaneously collect StE and fluorescence.
- Observed fluorescence depletion in the spectral window expected for StE emission.
Main Results:
- Fluorescence depletion was observed in the spectral window where StE signal was expected.
- The results indicate that StE emission does not follow a simple classical dipole pattern.
- Simultaneous fluorescence measurement calibrated the potential size of StE emission.
Conclusions:
- Stimulated emission directionality is dependent on the driving field, not a pure dipole radiation.
- This clarification is vital for optimizing microscope design and optical cooling.
- Understanding StE characteristics enables advancements in applications using small emitter arrays.
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