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Performing Spectroscopy on Plasmonic Nanoparticles with Transmission-Based Nomarski-Type Differential Interference Contrast Microscopy
Published on: June 5, 2019
Optical spectroscopy of conductive junctions in plasmonic cavities
O Pérez-González1, N Zabala, A G Borisov
1Donostia International Physics Center and Centro de Física de Materiales, Centro Mixto CSIC-UPV/EHU, Paseo Manuel Lardizabal 4, 20018 Donostia-San Sebastián, Spain.
Nano Letters
|August 12, 2010
Summary
Junction conductivity significantly alters nanoparticle dimer optical properties, revealing a new charge transfer plasmon. This suggests plasmonic cavities can probe molecular conductance at high frequencies.
Area of Science:
- Plasmonics
- Nanoparticle optics
- Molecular electronics
Background:
- Optical properties of nanoparticle dimers are sensitive to their environment.
- Conductive junctions introduce new phenomena in plasmonic systems.
Purpose of the Study:
- To investigate the impact of junction conductivity on the optical properties of nanoparticle dimers.
- To explore the emergence of charge transfer plasmons and their dependence on conductance.
- To present a physical model explaining the observed spectral features.
Main Methods:
- Theoretical modeling of nanoparticle dimers with conductive junctions.
- Analysis of optical spectra as a function of junction conductivity.
- Development of a physical model for spectral feature interpretation.
Main Results:
- Plasmon blueshift and broadening observed with increasing junction conductivity.
- Appearance of a low-energy charge transfer plasmon at high conductance.
- Charge transfer plasmon linewidth decreases with increasing conductance.
Conclusions:
- Junction conductivity strongly influences nanoparticle dimer optical spectra.
- Plasmonic cavities offer a potential method for probing molecular conductance at high frequencies.
- The findings provide insights into the interplay between plasmonics and molecular electronics.
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