Symmetry-sensitive plasmonic enhancement of nonlinear optical intensity in nano-micro hierarchical structures on silver

摘要

We created nano-micro hierarchical surface structures on Ag and measured their optical second harmonic generation (SHG) response. We found that the hierarchical surface structures can significantly modify the optical nonlinearity of the metal surfaces. The macroscopic symmetries of surface's shape influenced SHG. In addition, the observed SHG on Ag showed the contribution by the surface plasmon excitation. We also observed unique anisotropic enhancement of SHG in metal. We attribute our observations to both symmetry and surface plasmons on nano-micro hierarchical structures. Copyright (c) 2016 John Wiley & Sons, Ltd.