STED · Real Space-Time imaging and control of Electron Dynamics

The STED project aims at giving an important push to the scientific career of the applicant, in a timely and interdisciplinary topic: imaging the early stages of quantum motion of electrons at their natural space-time scales, i.e., with picometer and attosecond/femtosecond resolutions. The project will take place at IMDEA Nanoscience, a leading multidisciplinary research center dedicated to nanoscience and the development of nanotechnology applications in connection with innovative industries.Electron motion in molecular systems is responsible for natural processes such as photosynthesis, photooxidation, or electronic transport. It is also at the heart of novel technologies based on photovoltaic devices, artificial photosynthesis, molecular wires, etc. Understanding the underlying electron dynamics demands investigating these processes at their natural spatial and temporal scales. In the STED project, I will build a setup where a CW laser and few-femtosecond long laser pulses will be combined with a low-temperature STM. This setup will allow me to image and eventually control electron dynamics occurring in different molecular systems deposited on solid substrates at electronic time scales from hundreds of attoseconds to a few femtoseconds, with simultaneous sub-molecular spatial resolution. I will focus on investigating Rabi oscillations of individual phthalocyanine molecules, and charge-transfer processes between a donor and an acceptor phthalocyanine. The goals are to spectroscopically characterize the induced electron dynamics in real space with the CW laser, and subsequently provide the 'film' of the distribution of the electronic density in real time and real space with the pulsed laser source. This will allow me, e.g., to understand the origin of early sources of decoherences that reduce the efficiency of electronic transport, with possible implications in photovoltaics and quantum information technologies.