[13p-2F-1~16] 3.7 Laser processing

△ [13p-2F-9] Evidence of Surface Plasmon Polaritons on Si excited with a Femtosecond Laser Pulse

〇(M1)Masato Hagiya¹, Godai Miyaji¹ (1.TUAT)

Keywords:femtosecond laser processing,surface plasmon polaritons,silicon

Our research group has shown that the periodicity of nanostructures formed on solid surfaces with femtosecond (fs) laser pulses is attributed to the excitation of surface plasmon polaritons (SPPs). To observe the SPPs excited, the incident angle dependence of reflectivity change on Si grating with a spatial period of 1300 nm was measured with a single shot of the fs laser pulse at the center wavelength of 800 nm. With the p-polarized fs laser pulse at high fluence above the single-shot ablation threshold of Si, we observed the minimum of the reflectivity at the incident angle of 25 degrees, while we did not observe with the s-polarized pulse. This experimental results demonstrate that the SPPs can be excited on Si with the intense fs laser pulse.