Figure 2
From: Plasmonic waveguide design for the enhanced forward stimulated brillouin scattering in diamond

Electric field distributions of (a) E x and (b) E y components from cross-sectional view (x-y plane). Geometrical parameters are: H 0 = 250 nm, W 2 = 150 nm. The incident wavelength is 637 nm, which corresponds to the zero phonon line emission produced by nitrogen vacancy that is embedded in diamond.