Figure 5
The relation curve of electric field enhancement (a) and Raman enhancement factor (b) covering different Al2O3 thickness with the change of incident light wavelength. (c) Is the side view and top view of electric field distribution with different thickness Al2O3 (r0 = 1 ~ 4 nm). The excitation wavelength of the Raman enhancement factor and the electric field distribution diagram are both 665 nm. The distance between Au@Al2O3 dimer is fixed at 1 nm, and the radius R is set to 50 nm.
