7 research outputs found
Decay of dark and bright plasmonic modes in a metallic nanoparticle dimer
We develop a general quantum theory of the coupled plasmonic modes resulting
from the near-field interaction between localized surface plasmons in a
heterogeneous metallic nanoparticle dimer. In particular, we provide analytical
expressions for the frequencies and decay rates of the bright and dark
plasmonic modes. We show that, for sufficiently small nanoparticles, the main
decay channel for the dark plasmonic mode, which is weakly coupled to light
and, hence, immune to radiation damping, is of nonradiative origin and
corresponds to Landau damping, i.e., decay into electron-hole pairs.Comment: 9 pages, 3 figures; published versio
Nonradiative limitations to plasmon propagation in chains of metallic nanoparticles
We investigate the collective plasmonic modes in a chain of metallic
nanoparticles that are coupled by near-field interactions. The size- and
momentum-dependent nonradiative Landau damping and radiative decay rates are
calculated analytically within an open quantum system approach. These decay
rates determine the excitation propagation along the chain. In particular, the
behavior of the radiative decay rate as a function of the plasmon wavelength
leads to a transition from an exponential decay of the collective excitation
for short distances to an algebraic decay for large distances. Importantly, we
show that the exponential decay is of a purely nonradiative origin. Our
transparent model enables us to provide analytical expressions for the
polarization-dependent plasmon excitation profile along the chain and for the
associated propagation length. Our theoretical analysis constitutes an
important step in the quest for the optimal conditions for plasmonic
propagation in nanoparticle chains.Comment: 14 pages, 6 figures; v2: published versio
Nonradiative limitations to plasmon propagation in chains of metallic nanoparticles
This is the author accepted manuscript. The final version is available from the American Physical Society via the DOI in this recordWe investigate the collective plasmonic modes in a chain of metallic nanoparticles that are coupled by near-field interactions. The size- and momentum-dependent nonradiative Landau damping and radiative decay rates are calculated analytically within an open quantum system approach. These decay rates determine the excitation propagation along the chain. In particular, the behavior of the radiative decay rate as a function of the plasmon wavelength leads to a transition from an exponential decay of the collective excitation for short distances to an algebraic decay for large distances. Importantly, we show that the exponential decay is of a purely nonradiative origin. Our transparent model enables us to provide analytical expressions for the polarization-dependent plasmon excitation profile along the chain and for the associated propagation length. Our theoretical analysis constitutes an important step in the quest for the optimal conditions for plasmonic propagation in nanoparticle chains.CNRSAN