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arXiv · 2110.09224

Optical imaging and tracking of single molecules in ultrahigh vacuum

Tianyu Fang·Florian Elsen·Nick Vogeley·Daqing Wang
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Abstract

Molecule-surface interaction is key to many physical and chemical processes at interfaces. Here, we show that the dynamics of single molecules on a surface under ultrahigh vacuum can be resolved using fluorescence imaging. By adapting oil-immersion microscopy to a thin vacuum window, we measure the surface adsorption, translational and rotational diffusion of single perylene molecules on a fused silica surface with high spatial and temporal resolutions. Time-dependent measurements of the fluorescence signal allow us to deduce two characteristic decay time scales, which can be explained through a simplified model involving two adsorption states and five energy levels. The system presented in this work combines fluorescence imaging with essential ingredients for surface science and promises a platform for probing single molecule-surface interactions in highly defined conditions.

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Tianyu Fang, Florian Elsen, Nick Vogeley, Daqing Wang. 2021-10-18. Optical imaging and tracking of single molecules in ultrahigh vacuum. https://arxiv.org/abs/2110.09224

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