Ultrafast Dynamics and Non-Equilibrium Processes

Optical and Carrier Dynamics in Nanomaterials. A grand challenge in the scientific community targets control over manipulations of optical properties and electrical charges to achieve targeted or efficient energy transduction processes. The available manipulations of nanoscopic material features offer a tool to achieve insights that help afford such proficiency. Features such as new electronic states in quantum-confined semiconductors, hybridization of plasmonic transitions, and efforts to achieve efficient charge and energy transfers, are areas of focus in this area.

Engineered and Responsive Dynamics of Strain and Mechanical Motion. Goals in this area include learning to understand and predict the behavior of mechanical structures as their dimensions are reduced to the nanoscale. For some systems, stress and strain become disproportionally dominant in prescribing mechanical behavior especially where nonlinear effects increase due to the natural small limit of linear displacements. Opportunities abound to realize new functional properties through experimental understanding of dynamically driven nanostructures that extend the reach of multi-scale materials modeling to adequately predict behaviors even when one dimension of the material is only a few to a few hundred atoms thick.

Dynamics of Ordering and Response of Hierarchical Assemblies. The overarching goal of this thrust is to develop experimental techniques, both to probe structural evolutions in highly non-equilibrium nanoscale systems, and to produce and investigate dynamics influenced by the mesoscale, topological, or assembly-driven ordering of nanoscale materials. Regimes of interest include systems driven out of equilibrium by external fields, through chemical potential or near-phase transitions. The structure and dynamics of these systems can be diverse, driven by instabilities or metastable states formed from the competing interactions between constituent building blocks and their hierarchical arrangement. We combine real- and reciprocal-space imaging techniques with molecular dynamics simulation and AI-driven data processing to develop a better understanding of how these systems evolve, and correlate structural and dynamics information with the physical properties of the system to achieve advanced functionality.