| Abstract | Abstract
This paper presents a graphical user interface, based on modified
long-wavelength approximation me
thod (MLWA) to compute the
optical properties of core-shell nanoparticles. The validity of this
technique is verified by comparison to the exact solution (Mie
theory). For core-shell nanoparticles, when the shell thickness of a
core-shell particle is decreased, the plasmon resonance shifts to
longer wavelengths. This red shift is accompanied by an increase
in peak intensity. For coated spherical particles, we confirm that
our approach yields a correspondence with Mie theory and gives
an approximation error of less
than 2.8% for silica-gold and
silica-silver particles with outer diameters approaching 40nm and
26nm and inner diameters approaching 38nm and 24nm
respectively. Also the MLWA can give an acceptable degree of
accuracy 4.92% for larger part
icles of silica-gold with (inner-
outer) diameters 68-70nm at surface plasmon resonance
wavelength 1573nm. For this simulation run, the computation
time was less than 150.050 ms (Intel Pentium 4 CPU at 3GHz,
1.00GB of RAM), which includes calc
ulation of the polarizability
and all three cross-section plots of absorption, scattering and
extinction. This simulator provides a useful guide tool for optical
characterization experiments. |