Magneto-optical properties of chemically-synthesized nanoarchitectures made of non-magnetic metals: Electronic structures and magnetoplasmon

2017 Fiscal Year Final Research Report

• Project/Area Number: 15K04593
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Nanostructural chemistry
• Research Institution: Mie University (2017); University of Hyogo (2015-2016)
• Principal Investigator: Yao Hiroshi 三重大学, 工学研究科, 教授 (20261282)
• Project Period (FY): 2015-04-01 – 2018-03-31
• Keywords: 磁気円二色性 / マグネトプラズモン / 配位子保護金属ナノ粒子 / 局在表面プラズモン / ファラデー効果 / 魔法数 / 魔法数クラスター

Outline of Final Research Achievements

Magneto-optical (MO) properties of non-magnetic metal nanoparticles were examined by magnetic circular dichroism (MCD) spectroscopy. (1) In Ag nanospheres, a derivative-like MCD signal was observed. The magnetoplasmonic oscillation with a lower frequency provided a stronger MO amplitude compared to that with a higher frequency giving asymmetric bisignated lineshapes. (2) MO activity was demonstrated in Au nanoparticles. We found an efficient method to separate the effects of intraband Drude and interband transitions in MCD spectra using an approximation that the optical response of the nanoparticle with a size for the disappearance of LSPR is dominated by interband transitions. (3) In Ag nanoprisms, a derivative-like MCD signal was observed at the energy of dipolar LSPR. In contrast, that for in-plane or out-of-plane quadrupolar LSPR showed a single peak that corresponds to the position of its extinction maximum, suggesting that MCD spectroscopy is effective for easy identification.

Free Research Field

物理化学