[20p-S622-1~19] 3.12 Nanoscale optical science and near-field optics

[20p-S622-15] Optical enhance detection of picosecond mechanical vibrations using nanofocused surface plasomon polaritons

〇Motonobu Tomoda^1,2, Xiang Chen², Oluwaseyi Balogun² (1.Hokkaido Univ., 2.Northwestern Univ.)

Keywords:surface plasomon poralitions,picosecond ultrasonics

We measured picosecond scale mechanical vibrations of paired nanoscale pillar allay samples using a pump probe technique. The sample configurations consist of a thin gold film on PMMA nano- ellipsoidal shape pillars on silicon substrate. By changing linear polarized direction of probe light, not only breathing modes but also second harmonic mode of the breathing modes were detected. This is explained by nonlinearity of surface plasmon polaritons enhanced between nano-pillars towards the pillar distances.