Related Experiment Video
Updated: Jun 25, 2025
07:39
Determination of the Excitation and Coupling Rates Between Light Emitters and Surface Plasmon Polaritons
Published on: July 21, 2018
6.8K
Influence of Quadrupolar Molecular Transitions within Plasmonic Cavities
Junyang Huang1, Oluwafemi S Ojambati1, Clàudia Climent2,3
1NanoPhotonics Centre, Cavendish Laboratory, Department of Physics, JJ Thompson Avenue, University of Cambridge, Cambridge CB3 0HE, U.K.
ACS Nano
|May 24, 2024
Summary
Researchers enhanced light emission from dark molecular transitions using plasmonic nanocavities. This breakthrough, exceeding 4 orders of magnitude, unlocks new possibilities for spectroscopy and sensing applications.
Area of Science:
- Nanophotonics
- Molecular Spectroscopy
- Plasmonics
Background:
- Optical nanocavities control light emission from molecules and semiconductors.
- Dark transitions are typically light-forbidden and difficult to excite.
Purpose of the Study:
- Investigate amplified photoluminescence from dark transitions of beta-carotene molecules in plasmonic nanocavities.
- Explore enhancement mechanisms beyond conventional dipolar interactions.
Main Methods:
- Integrating beta-carotene monolayers into nanoparticle-on-mirror nanostructures.
- Utilizing Fourier-plane scattering spectroscopy to analyze photoluminescence excitation.
- Performing quantum chemistry calculations and electromagnetic simulations.
Main Results:
- Achieved photoluminescence enhancements exceeding 4 orders of magnitude for a dark transition.
- Identified resonance with a higher-order plasmonic cavity mode supporting strong field gradients.
- Demonstrated the significant role of quadrupole moments in photoluminescence enhancement within cavities.
Conclusions:
- Plasmonic nanocavities can access and enhance optically inactive transitions.
- The interplay of Franck-Condon quadrupole and Herzberg-Teller dipole contributions is crucial.
- This approach offers potential for advanced spectroscopy and sensing technologies.
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