Control of magnetic properties by "hot-spot" electric field generated by localized-surface plasmon resonance

2021 Fiscal Year Final Research Report

• Project/Area Number: 18KK0407
• Research Category: Fund for the Promotion of Joint International Research (Fostering Joint International Research (A))
• Allocation Type: Multi-year Fund
• Research Field: Electronic materials/Electric materials
• Research Institution: Chiba Institute of Technology
• Principal Investigator: Yasukawa Yukiko 千葉工業大学, 工学部, 准教授 (10458995)
• Project Period (FY): 2019 – 2021
• Keywords: 電気電子材料 / ナノ磁性構造体 / 磁気光学効果 / 金属ナノ粒子 / プラズモン / プラズモン増強電界

Outline of Final Research Achievements

We studied "magneto-plasmonic materials" consisting of a magnetic-thin film and self-organized noble-metal nanoparticles. The present study was carried out with a collaboration of Dr. J. G. Lin et al. of National Taiwan University. The main objective in this study was to investigate the optical wavelength dependence of enhanced-electric field originated from localized-surface plasmon resonance (LSPR). LSPR is generated by noble-metal nanoparticles. The quantification of the enhanced-electric field by LSPR is also one of the main objectives in the present study.
We evaluated the LSPR-enhanced electric field by means of several different spectroscopic techniques. The results clarified that the electric-field intensity is significantly enhanced at LSPR wavelength compared to other wavelengths.

Free Research Field

磁性材料

Academic Significance and Societal Importance of the Research Achievements

これまでは表面プラズモン共鳴やLSPRによる電場の増強は理論計算等から説明されてきた。本研究はこれを実際の物質において実験から観測した研究として意義がある。また物質中で励起するLSPRによってどの程度電場が増強するかの定量を行ったことも学術的に大きな意義がある。
今回の研究ではLSPR励起波長では他の波長帯と比較して数桁に及ぶ電場強度の増大を明らかにした。この増強電場を利用することにより、物質の様々な物理的物性を増大あるいは変調でき、新奇物理的物性を開拓できる可能性がある。