In this paper, the near-field optical properties of nanoparticles, which are deposited on Titanium (Ti) substrate and irradiated by laser pulses with wavelength ranging from 0.4 nm to 1.2 nm, are presented by using numerical simulations. Considering the near-field electric intensity distribution, the enhancement factor (E/E0)2 and the peak enhancement value (Emax/E0)2, we compared the difference between gold particle with 200 nm diameter and SiO2 particle with 2μm diameter. It is found out that, the intensity distribution around the contact point between particles and Ti substrate shows as an annular. The enhancement factor generated by 200 nm gold particle is over 10 times larger than 2 μm SiO2 particle after irradiated by incident light with the same wavelength. In experiment section, using 200 nm diameter gold particles, we fabricated nanoholes on Ti-6Al-4V surface with diameter about 170 nm when laser pulse energy was set as 0.354 J/cm2. The diameter of nanoholes is corresponding to the previous simulation results in this paper.
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