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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.
Arxiv
|January 10, 2024
Summary
Stimulated emission (StE) imaging is explored, revealing its emission pattern is not a simple dipole. This finding is crucial for optimizing StE microscopy and related applications.
Area of Science:
- Optics and Photonics
- Molecular Imaging
- Quantum Optics
Background:
- Stimulated Emission (StE) offers advantages in speed, coherence, and resolution over fluorescence imaging but remains underutilized.
- The radiation pattern and directionality of StE from single molecules are not fully understood, with prevailing ideas suggesting dependence on the driving field or a pure dipole pattern.
Approach:
- Introduced the StE driving field (probe) at an angle using total internal reflection to prevent interference from incident probe light and its reflections.
- Utilized a non-collinear detection configuration that also collects fluorescence, enabling simultaneous measurement of fluorescence depletion.
- Observed fluorescence depletion in the spectral window where StE signal increase was expected for a dipole emitter.
Key Points:
- The study investigated the radiation pattern of Stimulated Emission (StE) from single molecules.
- A non-collinear detection setup with total internal reflection was employed to isolate StE signals.
- Fluorescence depletion was observed, indicating StE does not radiate as a simple classical dipole.
Conclusions:
- The emission pattern of Stimulated Emission (StE) is not a pure dipole and depends on the driving field.
- This clarification is essential for designing advanced StE microscopes and developing applications in optical cooling and emitter arrays.
- Understanding StE's directional characteristics is key to unlocking its full potential in imaging and beyond.
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