Figure 2

The enhancement factors (left) and scattering cross section (right) for R6G molecule placed symmetrically between two AgNPs with different radius and separations. The energy of the incident laser is 2.45 eV. (a,c,e and g) Are the enhancement factors with r = 20 nm, 40 nm, 60 nm, and 80 nm, respectively, (b,d,f,h) are the scattering cross section with r = 20 nm, 40 nm, 60 nm and 80 nm, respectively. The insert of (a) shows the typical electric field distribution of the AgNPs dimer.