Figure 3

(a–e) SEM images of Au nanostructures fabricated from a 40-nm film on a SiO₂ substrate at various pulse energy levels: a 0.020 μJ, b 0.022 μJ, c 0.025 μJ, d 0.027 μJ, e 0.032 μJ. f–h SEM images of large-area Au nanodisc, nanodome, and nanoparticle arrays corresponding to the nanostructures shown in a, b, and d. Right lower insets: enlarged SEM images of typical nanostructures from the arrays (scale bar, 200 nm). Right upper insets: Fourier spectra of the single nanostructure SEM images.