Project Area
A
Coherent electron dynamics
from single molecules to molecular solids
Project A1
Quantum coherence in single and coupled molecules
J. Repp
R. Huber
We aim to directly visualize and control the quantum coherent motion of single electrons and atoms in single and coupled molecules. To this end, we will employ our lightwave scanning tunnelling microscope (LW-STM) that allows a combined sub-picosecond and Ångström spatio-temporal resolution. We will develop methods to substantially increase the temporal resol-ution, which is crucial for the observation of intramolecular dynamics. Fundamental insights into the dynamics of intra- and intermolecular coherence and decoherence mechanisms on atomic length scales are expected.
Project A2
Light driven quantum many-body systems in the ultimate space-time limit
M. Grifoni
F. Evers
Using realistic modelling of correlated molecular and solid-state systems, time-depen-dent properties of key observables will be evaluated through generalized quantum master equa-tions (GQME) for the reduced density operator, which can cope with interactions, interference and collective phenomena at the many-body level. We will simulate lightwave scanning tunnelling microscopy (LW-STM) setups and investigate the propagation of collective excitations in low-dimensional superconductors. Further, we aim at setting the conditions under which supercon-ductivity can be steered by light in selected molecular crystals.
Project A3
Ultrafast electron transport in crystalline nanomaterials
I. Gierz
M. Grifoni
With their ability to image electron dynamics both in real and reciprocal space, momen-tum microscopes recently turned into an indispensable tool for ultrafast materials science. We will implement a new time-of-flight photoemission electron microscope (TOF-PEEM) with femtosec-ond pump and probe pulses, variable from the visible to the mid-infrared (MIR) and from the ultraviolet (UV) to the extreme ultraviolet (XUV) spectral range, respectively, to investigate ultra-fast charge transfer across different van-der-Waals interfaces and to explore possible light-induced coherent transport in molecular solids.
Project A4
Cooperativity in ultrafast electron dynamics – interfacial polarons, polaritons and superconducting collectivism
F. Evers
I. Gierz
Interfaces can shape ultrafast electron dynamics in intriguing ways. Specifically collective interface excitations, which reflect the reduced spatial dimensionality of the system, can influence the charge response of adsorbates, such as functionalized molecules. Cooperative phenomena of this kind can now be visualized even experimentally on extreme time and length scales. Thus motivated, we here study the interplay of local entities, e.g., single molecules, with lattice and collective electronic degrees of freedom of the substrate; we simulate the time evolution of surface-charge excitations focusing on superconducting substrates. Ab-initio and custom tailored new computational tools will be employed.