We describe a new type of nanohole processing technique mediated with surface plasmon enhanced localized near-field in the vicinity of the gold nanoparticles excited by a femtosecond laser. The numerical analysis of near-field optical properties based on 3D FDTD simulation and experimental results of the processed nanoholes are presented. For the patterning of the various kinds of substrate surface, the near-field enhancement factors and intensity distributions are studied on the different substrates: dielectrics, semiconductors and metals. The experimental results of nanohole ablation validated the simulated results. The field enhancement factors become quite large on semiconductor and metallic substrate due to the large image charge effect, whereas that on dielectric substrate is quite small. The resonant wavelength for the near-field enhancement inside the substrate is significantly shifted from that of the particle in vacuum and it strongly depends on the optical constants of the substrate due to the surface plasmon polaritons nature. The anomalous energy flow such as optical vortex and bifurcation is found to occur around the strongly enhanced area inside the substrate. As for the processing with arrayed nanoparticles, the interparticle distance is a crucial parameter due to the nearfield coupling effect between particles, which governs the magnitude of the field enhancement and the near-field distribution on the substrate surface. This nanohole processing technology is also applied for the nanoablation of glass film deposited on different substrates. The processing properties are strongly dependent on the substrate materials under the film, which reveal the plasmonic coupling effect between the particle and substrate. Finally, we will compare the near-field properties between the gold particle and dielectric particle on the substrates using Mie scattering theory.
|Title of host publication||Gold Nanoparticles: Properties, Characterization and Fabrication|
|Publisher||Nova Science Publishers, Inc.|
|Number of pages||32|
|Publication status||Published - 2011 Jan|
ASJC Scopus subject areas
- Physics and Astronomy(all)
- Materials Science(all)