Abstract We present a microscopic model describing the transition to a strong coupling regime for an emitter resonantly coupled to a surface plasmon in a metal–dielectric structure. We demonstrate that the shape of scattering spectra is determined by an interplay of two distinct mechanisms. First is the near-field coupling between the emitter and the plasmon mode which underpins energy exchange between the system components and gives rise to exciton-induced transparency minimum in scattering spectra prior to the transition to a strong coupling regime. The second mechanism is the Fano interference between the plasmon dipole and the plasmon-induced emitter’s dipole as the system interacts with the radiation field. We show that the Fano interference can strongly affect the overall shape of scattering spectra, leading to the inversion of spectral asymmetry that was recently reported in the experiment.
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Exciton-induced transparency in hybrid plasmonic systems
We present a microscopic model for exciton-induced transparency (ExIT) in a hybrid system
comprised of an emitter resonantly coupled to a surface plasmon in a metal-dielectric structure.
We obtain an effective optical polarizability of such a system with coupling between the system
components expressed in terms of energy transfer rates. We demonstrate that, in the weak coupling
regime, the underlying mechanism of ExIT is the energy exchange imbalance between the plasmon
and the emitter in a narrow frequency region. We derive in analytic form a frequency-dependent
function that accurately describes the shape and amplitude of the transparency window in scattering
spectra, supported by numerical calculations.
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- Award ID(s):
- 1856515
- NSF-PAR ID:
- 10170517
- Date Published:
- Journal Name:
- arXiv:2007.04534v1
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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null (Ed.)We present a microscopic model describing the transition to strong coupling regime for an emitter resonantly coupled to a surface plasmon in a metal-dielectric structure. We demonstrate that the shape of scattering spectra is determined by an interplay of two distinct mechanisms. First is the near-field coupling between the emitter and the plasmon mode which underpins energy exchange between the system components and gives rise to exciton-induced transparency minimum in scattering spectra prior the transition to strong coupling regime. The second mechanism is Fano interference between the plasmon dipole and the plasmon-induced emitter's dipole as the system interacts with the radiation field. We show that the Fano interference can strongly affect the overall shape of scattering spectra, leading to the inversion of spectral asymmetry that was recently reported in the experiment.more » « less
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