Our group uses and develops advanced multidimensional ultrafast spectroscopic methods to study complex systems such as natural photosynthetic complexes, liquids, solution, and nanoscale systems such as single-walled carbon nanotubes.
In natural photosynthetic systems we aim to define the design principles underlying their remarkable .quantum efficiencies, and to use these principles to aid in the design of robust and efficient artificial photosynthetic devices. Natural systems are also regulated in response to external conditions, such as light levels, and one of the key components of Photosystem II is regularly repaired. We plan to understand the control system at the molecular level by combining molecular genetics biochemistry, modeling, and ultrafast spectroscopy through collaboration with Professor K. K. Niyogi. We have recently shown, using two-dimensional electronic spectroscopy, that long lived electronic quantum coherence exists in photosynthetic light harvesting complexes. We are exploring the implications of quantum coherence for photosynthesis and for quantum information science.
The electronic properties and excited state dynamics of nanoscale materials with significant quantum confinement effects yield a rich range of properties and potential applications. We aim to understand these properties with a particular current emphasis on single-walled carbon nanotubes via non-linear ultrafast spectroscopy and theoretical modeling.
The modern theoretical description of photochemical processes, in particular what determines which products are formed, has at its core relaxation through conical intersections. Yet very little experimental information is available on such processes. Two dimensional electronic spectroscopy has the potential to provide a window into these processes and experiments to explore conical intersection dynamics are under development.
Ultrafast multidimensional electronic spectroscopy is in its infancy with many potential ways to enhance resolution, sharpen the information content and extract specific dynamical pathways (e.g., those that involve only coherence). My group continues to develop new spectroscopic methods and the theoretical tools for their analysis.