1 research outputs found
High-Energy Surface and Volume Plasmons in Nanopatterned Sub-10 nm Aluminum Nanostructures
In this work, we use electron energy-loss
spectroscopy to map the
complete plasmonic spectrum of aluminum nanodisks with diameters ranging
from 3 to 120 nm fabricated by high-resolution electron-beam lithography.
Our nanopatterning approach allows us to produce localized surface
plasmon resonances across a wide spectral range spanning 2–8
eV. Electromagnetic simulations using the finite element method support
the existence of dipolar, quadrupolar, and hexapolar surface plasmon
modes as well as centrosymmetric breathing modes depending on the
location of the electron-beam excitation. In addition, we have developed
an approach using nanolithography that is capable of meV control over
the energy and attosecond control over the lifetime of volume plasmons
in these nanodisks. The precise measurement of volume plasmon lifetime
may also provide an opportunity to probe and control the DC electrical
conductivity of highly confined metallic nanostructures. Lastly, we
show the strong influence of the nanodisk boundary in determining
both the energy and lifetime of surface plasmons and volume plasmons
locally across individual aluminum nanodisks, and we have compared
these observations to similar effects produced by scaling the nanodisk
diameter