부산대학교 도서관

Plasmonic–photonic crystals that consist of SiO2 nanosphere opals decorated with ≈100 nm wide silver caps are fabricated by self‐assembly methods. Optical measurements of the samples show anomalous suppression of reflectivity in the spectral range of the photonic bandgap of the opal structure, which results in an inverted reflection spectrum compared to that of the bare opal structure. This suppression occurs over a range of incident angles and for opal structures with different lattice constants. The experimental observations suggest that the suppression results from the excitation of localized surface plasmon on Ag nanocaps. Results of numerical simulations with rigorous coupled wave analysis and the finite difference time domain method suggest that the coupling between the excitation of Ag‐cap surface plasmon and the scattering of the incident light inside the opal lead to the suppression of the opal reflection at the photonic bandgap wavelengths. [ABSTRACT FROM AUTHOR]