[18p-P9-1~34] 3.12 Nanoscale optical science and near-field optics

[18p-P9-18] Propagation loss of surface plasmon polaritons on Si excited with femtosecond laser pulses

〇Godai Miyaji¹, Masato Hagiya¹ (1.Tokyo Univ. of A & T)

Keywords:surface plasmon polariton, femtosecond-laser processing, silicon

Intense near-fields of surface plasmon polaritons (SPPs) excited with femtosecond laser pulses can sculpt nanometer-size structures on various kinds of solid materials through ablation. To control the formation, the characteristic properties of SPPs need to be understood. In this work, we have measured the full width at half maximum (FWHM) of surface plasmon resonance curves of Si gratings with p-polarized 100-fs laser pulses. In the reflectivity measurements, the FWHM decreased monotonously in increasing the laser fluence. The experimental results and calculation for model targets have shown that SPPs with low internal damping can be excited with the fs pulse at higher fluence.