Biomedical Engineering Reference
In-Depth Information
8.3 SPP Coupling via Shared Circulating Powerflow
Another interesting class of plasmonic waveguiding platforms is a
MIM structure, which guides optical energy along a narrow slot
between two metal interfaces. In such plasmon slot waveguides,
optical mode volumes can be reduced to sub-wavelength scales
whilesufferinglowdecayevenforfrequenciesfarfromtheplasmon
resonance [52]. A schematic of the MIM plasmon slot waveguide
is shown in Figs. 8.4a and 8.5a, and the dispersion characteristics
Figure 8.4
Shared circulating powerflow of the odd SPP mode in a MIM
plasmon slot waveguide. (a) Schematic of the MIM waveguide and the
coordinate system. (b) The dispersion characteristics of the SPP modes
supported by the structure in (a). The green curve is the dispersion branch
corresponding to the odd mode. (c,d) The electric (c) and magnetic field
componentsoftheoddSPPmode.(e)Thetime-averagedopticalpowerflow
in the MIM waveguide. (f) The corresponding instantaneous powerflow at
t
10
15
rad/s.
=
0. All field distributions were calculated at
w
=
4.974
×
