Autonomous plasmonic nanomotors responding to surface molecular adsorption

2022 Fiscal Year Final Research Report

• Project/Area Number: 19H02533
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 28010:Nanometer-scale chemistry-related
• Research Institution: The University of Tokyo
• Principal Investigator: Tanaka Yoshito 東京大学, 生産技術研究所, 助教 (50533733)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: プラズモニックセンサー / 光圧 / プラズモニックナノ構造 / 金ナノ構造 / ナノ光圧計測

Outline of Final Research Achievements

Based on the highly sensitive response of localized plasmon resonance associated with molecular adsorption on metal surfaces, we have studied the plasmon-induced optical force as the driving force of autonomous nanomotors. We found plasmonic nanostructures that can not only change the magnitude of the optical force with high sensitivity according to the environmental refractive index, but also change the sign (direction) of the force. In addition, we proposed and developed a novel method to quantitatively measure optical force on highly anisotropic and complex nanostructures, and demonstrated that optical force and torque can be measured with the highest accuracy in the world. Furthermore, we worked on radiation control of nonlinear light scattering to improve the sensitivity of the optical force response, and found nanostructures that produce unidirectional second harmonic waves (SHG) or radially polarized SHG.

Free Research Field

ナノフォトニクス

Academic Significance and Societal Importance of the Research Achievements

局在プラズモン共鳴の優れた局所センサー機能によってパッシブ制御可能な光圧駆動ナノモーターは、ナノマシンの研究に新しい道を拓くものであり、Lab on a chipや化学ナノイメージング、ライフサイエンスなどへの応用だけでなく、ナノ医療、高機能光反応・光触媒、高効率光エネルギー変換等にむけてブレークスルーとなりうる新しい展開が期待できる。また本研究は、局在プラズモンと分子の相互作用を光運動量変化という新しい視点から研究するものであり、光運動量変化を決めている局在プラズモンの位相空間分布に顕れる新奇相互作用や新しい物理の発見につながると期待される。