Probing of Ultrafast Plasmon Dynamics on Gold Bowtie Nanostructure Using Photoemission Electron Microscopy

• Published in: Chinese physics letters Vol. 32; no. 6; pp. 61 - 65
• Main Author: 秦将 季博宇 郝作强 林景全
• Format: Journal Article
• Language: English
• Published: 01.06.2015
• Subjects: Dynamics; Electron microscopy; Excitation; Lasers; Nanostructure; Photoemission; Plasmons; Tips; 光电; 发射电子显微镜; 泵浦-探测; 直接成像; 等离子体动力学; 纳米结构; 脉冲等离子体; 飞秒激光脉冲
• ISSN: 0256-307X; 1741-3540
• DOI: 10.1088/0256-307X/32/6/064202

We report the direct imaging of plasmon on the tips pulses and probing of ultrafast plasmon dynamics by of nano-prisms in a bowtie structure excited by 7 fs laser combining the pump-probe technology with three-photon photoemission electron microscopy. Different photoemission patterns induced by the plasmon effect are observed when the bowties are excited by s- and p-polarized femtosecond laser pulses. A series of images of the evolution of local surface plasmon modes on different tips of the bowtie are obtained by the time-resolved three-photon photoemission electron microscopy, and the result discloses that plasmon excitation is dominated by the interfer- ence of the pump and probe pulses within the first 13 fs of the delay time, and thereafter the individual plasmon starts to oscillate on its own characteristic resonant frequencies.