The interaction of light and matter plays a fundamental role in many natural processes, such as photosynthesis, vision, and bioluminescence, and has been pivotal in the development of photovoltaics, lasers, and optical communications. At the heart of chemical reactivity lies the ultrafast motion of electrons within molecules, which holds the promise for future technological advances. However, this electronic motion occurs on an extremely fast timescale, femtoseconds, and within spatial scales on the order of picometers.
To better understand electron dynamics inside molecules, there is a need for novel experimental tools that offer simultaneous femtosecond temporal and picometer spatial resolutions, enabling direct observation of light-matter interactions at their natural scales. Existing European facilities predominantly use ultrashort light sources that provide spatially averaged information, leaving a gap in local, real-time imaging capabilities.
The STED project addresses this gap by focusing on a complementary, so far barely explored approach: to image ultrafast electronic motion in individual molecules in real time but also in real space, with femtosecond and picometer resolutions, respectively, by combining ultrashort laser pulses with a scanning tunneling microscope (STM). The project addresses two key technological challenges: (1) the creation of hybrid light-matter quantum states in strongly coupled molecule-cavity systems, and (2) the detailed investigation of charge transfer processes between individual donor and acceptor molecules.
This research program positions the STED project to advance the frontiers of nanoscale quantum science and facilitate the development of transformative technologies in quantum information processing, ultrafast photonics, and energy-efficient nanoscale devices.
