Optical Imaging and Tracking of Single Molecules in Ultrahigh Vacuum

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 thin window, measure adsorption, translational rotational diffusion perylene fused silica with high spatial temporal resolution. Time-dependent measurements signal allow us deduce two characteristic decay time scales, which explained through simplified model involving adsorption states five energy levels. The system presented in this work combines imaging essential ingredients for science promises platform probing molecule-surface interactions highly defined conditions.