surface-enhanced raman scattering (sers) on 1d nano-gratings

Surface-enhanced raman scattering (sers) enhancement factor (ef) is among the major applications of surface plasmon polaritons (spp’s). in this work, the sers ef of 1d rectangular and sinusoidal-shaped gold (au) grating structures has been designed and optimized on au film using comsol multiphysics (5.3a) rf module taking glass as substrate. the 1d grating models are simulated by variation in slit width ranging 200–600 nm while other parameters including periodicity of 700 nm and au film thickness of 50 nm remained fixed. in order to study the several phenomena including enhanced optical transmission and sers ef, the transmission and electric field spectra have been obtained from both types of grating structures. in agreement with fundamental plasmonic mode, the slit width of two-thirds of the periodicity found to be optimum for sers ef. remarkable value of sers ef is obtained in the case of a sinusoidal au grating device (6.4 × 109) which is calculated to be five times that of the rectangular grating (1.2 × 109). these devices are also the fingerprints of molecules, hence find applications in biosensing, pollution control, and chemical and food industry.