metallic core-shell photonic crystals for surface-enhanced raman scattering (sers)

Metallic core-shell substrate is specially used to serve ultrasensitive molecular detection down to concentration of micromolar level based on surface-enhanced raman spectroscopy (sers). calculations show that the amorphous poly(methyl methacrylate) (pmma) photonic crystals incorporated with metal nanoparticles which is either gold or silver nanoparticles can significantly increase the electromagnetic fields at the air dielectric interface, leading to remarkable raman enhancement. corresponding experiments and characterizations show the characteristic and performance of core-shell structures which present an excellent sensitivity, reproducibility and stability to act as sers substrate.