Surface plasmons induced from periodic silver island arrays

• Main Authors: Lai Chiau Yuan, 賴巧原
• Other Authors: Lo Kuang Yao
• Format: Others
• Language: en_US
• Online Access: http://ndltd.ncl.edu.tw/handle/41275769930745414152

碩士 === 國立嘉義大學 === 電子物理學系光電暨固態電子研究所 === 100 === Abstract This thesis studied reflective second harmonic generation (RSHG) and Attenuated Total Reflection (ATR) from periodic silver nano-island arrays (PSNIA). We adopted PSNIA, silver thin film, and the combination of PSNIA and thin film to these experiments. An attempt of our work is to find the possibility of surface plasmons effect involving optical response of PSNIA samples. In RSHG experiment, the peak position and magnitude is obviously different from the Ag film. From PSNIA’s area proportion relative to thin film, we expected that PSNIA’s intensity is 5% of thin film. But, the experiment result is greater than expected one. The possibility is PSNIA create a reciprocal lattice vector which satisfies the phase-matching condition to couple surface plasmons (SPs). At the same time, this result was proved by finite-difference time-domain (FDTD) simulation. In ATR experiment, PSNIA is made at the bottom of SF11 prism with a spacing with holder to avoid the damage and backlight. Form a configuration of three layers, prism (SF11)/ PSNIA/air. Due to PSNIA is not a flat thin film, ATR spectrum will appear many dips. The sources of dips may come from surface plasmon resonance (SPR) or diffraction. Here, rigorous coupled wave analyze (RCWA) was used to prove the experimental result. Under identical structure with silver or dielectric, we do the comparison of these two ATR spectrums and find out the main mechanism. Above work, SPR effect in PSNIA would be clearer.