Ultrafast single molecule videography with sub-Ångström resolution
Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
Final Report Abstract
This project successfully explored the ultrafast dynamics of individual molecules directly in space and time, achieving significant advancements in atomic-scale temporal and spatial res-olution. Building on prior successes of lightwave-driven scanning tunnelling microscopy, the project delivered exceptional outcomes. One of the highlights was the study of electron-driven tautomerization using lightwave-driven action spectroscopy. The hydrogen tautomerization in naphthalocyanine molecules was inves-tigated, demonstrating the ability to trigger and control chemical reactions on sub-picosecond timescales by varying laser field strengths. These experiments also revealed intriguing dynamics influenced by the delay time between laser pulses, representing a leap forward in time-resolving chemical reactions on atomic length scales. To push temporal resolution further, the team developed new concepts in lightwave-driven scanning tunnelling microscopy using mid-infrared laser pulses. This enables future experi-ments exploring dynamics on attosecond timescales. The project also introduced ultrafast tunnelling spectroscopy, combining atomic spatial resolu-tion, femtosecond temporal resolution, and energy resolution. Using this method, the energy shifts of atomic-scale defect states after excitation were tracked, providing unprecedented in-sights into electronic dynamics. This breakthrough was featured as “Ultrafast Tunnelling Spec-troscopy” on the cover of Nature Photonics (2024). Another highlight was the development of a new contrast mechanism termed Near-field Optical Tunnelling Emission (NOTE) microscopy. This technique allows sub-cycle-resolved observa-tion of tunnelling dynamics at atomic scales, even in semiconductors and insulators like tungsten diselenide. By integrating NOTE microscopy with lightwave STM, the project demonstrated a radically new approach to studying light-matter interactions and nonlinear optics on atomic scales, paving the way for future innovations. These results, published in high-profile journals such as Nature, represent a major leap forward in understanding the ultrafast world of molecules and materials. The project paves the way for exciting new technologies and scientific discoveries in chemistry, physics, and beyond.
Publications
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All-optical subcycle microscopy on atomic length scales. Nature, 629(8011), 329-334.
Siday, T.; Hayes, J.; Schiegl, F.; Sandner, F.; Menden, P.; Bergbauer, V.; Zizlsperger, M.; Nerreter, S.; Lingl, S.; Repp, J.; Wilhelm, J.; Huber, M. A.; Gerasimenko, Y. A. & Huber, R.
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Ultrafast atomic-scale scanning tunnelling spectroscopy of a single vacancy in a monolayer crystal. Nature Photonics, 18(6), 595-602.
Roelcke, C.; Kastner, L. Z.; Graml, M.; Biereder, A.; Wilhelm, J.; Repp, J.; Huber, R. & Gerasimenko, Y. A.
