Biomedical Engineering Reference
In-Depth Information
Figure 15.18
(a) Representative SEM image of Aligned Antenna Dimer
(Single Antenna Arm Dimensions: 180 nm
×
120 nm
×
60 nm; Interparticle
Gap:20nm)(Scalebar:100nm);(b,c)2Dfieldenhancement(ratiobetween
the local and incident electric field) plots generated, at the resonance, on
a plane parallel to the substrate that cuts the structure in the center, in
condition of normal incident plane wave polarized respectively parallel to
structure long and short axis.
In perspective of engineering a plasmon-based device for
non-linear spectroscopy, for example, surface-enhanced Raman
spectroscopy (SERS), the chance of having a parameter, able to
modulate the hot spot intensity, ideally from a maximum value to
zero, would be a great advantage in order to reduce the Raman
signal-to-noise ratio by collecting, at zero-field condition, a precise
background signal. On the other hand the necessity of further
amplifying hot spot intensities requires decreasing the interparticle
