Fig. 6
(Reprinted with permission from Ref. [53])
Optimized WG length Lopt for maximum spatially averaged Raman enhancement factor (AEF) for the case of forward scattered signal collection, as a function of wavelength for the Ag plasmonic slot WG (PSW) with gap width g = 50 nm, and other WGs obtained by a varying the gap width g: Ag PSW with gap width g = 100 and 20 nm, b varying the metal filling fraction fm: Ag-Si3N4 HM slot WG (HMSW) with fm = 0.8 and 0 0.5, and c changing the WG type: Ag-Si3N4 hybrid plasmonic slot WG (HPSW) and Si3N4 dielectric slot WG (DSW). Each marker indicates a specific Stokes or anti-Stokes wavelength corresponding to one of the Raman modes. The vertical dotted line indicates the pump wavelength at λ0 = 785 nm.