Theoretical study of photoinduced force scanning microscopy for observation of excited states of single molecules

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K14554
• Research Category: Grant-in-Aid for Early-Career Scientists
• Allocation Type: Multi-year Fund
• Review Section: Basic Section 30020:Optical engineering and photon science-related
• Research Institution: Osaka Research Institute of Industrial Science and Technology (2023); Kitasato University (2021-2022)
• Principal Investigator: Yamane Hidemasa 地方独立行政法人大阪産業技術研究所, 和泉センター, 研究員 (10867823)
• Project Period (FY): 2021-04-01 – 2024-03-31
• Keywords: 光物性理論 / 光マニピュレーション / PiFM / 光圧 / キラリティ / superchiral field / ナノ物質 / 数値解析

Outline of Final Research Achievements

In this study, we successfully analyzed the optical response of molecules interacting with localized plasmons by incorporating the internal structure of molecules from their wavefunctions. Based on our computational method, we analyzed electromagnetic field response of Photoinduced Force Microscopy (PiFM) measurements and collaborated with experimental researchers to successfully conduct PiFM experimental measurements on a pentacene molecular film on a silver substrate. Furthermore, we were able to evaluate the optical pressure and rotational torque acting on the molecules, demonstrating the potential for enantioselective optical trapping at the single-molecule level and the functionality of a new chemical analysis method, "Plasmon TLC" method, which combines optical tweezers with thin-layer chromatography (TLC), through the theoretical analysis developed in this study.

Free Research Field

光物性理論

Academic Significance and Societal Importance of the Research Achievements

本研究の成果として、原子スケールの分解能を持つPiFMを用いて、単一分子の電子遷移や光学応答を精密に観測・解析することが可能となった。さらに、局在プラズモン中のキラル分子の光学応答を解析し、単一分子レベルでのエナンチオ選択的光トラッピングの可能性を示したことは、化学および生物学分野における分子認識や分子操作の新しい方法を提供するのもであある。これらの成果から得られる知見はナノテクノロジー、化学分析、バイオテクノロジーの分野における基礎研究および応用研究の両面に寄与するものである。