The principles governing charge and energy transport in molecular materials - from novel organic semiconductors to bioenergetic membranes - are often obscured by the complex interplay of structural heterogeneities, interfaces, and disorder on the nanometer-to-micron length scale (i.e., the mesoscale). Far from being a hinderance, it is exactly the spatial and temporal heterogeneities that realize their functional properties. The Mesoscience Lab develops new theoretical and computational tools to simulate the mesoscale dynamics of
[Mesoscale Quantum Dynamics] novel heterogeneous molecular semiconductors where quantum processes can occur on anomalously long length and timescales, and
[Photosynthetic Membranes] densely packed, dynamic photosynthetic membranes that convert sunlight into chemical energy.
We explore how the thylakoid membrane is regulated in response to environmental perturbations, such as light or nutrient stress. The change in membrane organization causes changes to both the light and dark reactions of photosynthesis. We build computational tools to model the interaction between membrane organization and the chemical reactions supporting photosynthesis. We apply a broad range of computational tools to this problem - sometimes we are solving the quantum dynamics of light harvesting, other times we are simulating classical processes like molecular diffusion in the membrane environment. We always connect our work with broad range of experimental measurements from structural biology, spectroscopy, and physiology.
Mesoscale quantum dynamics
We are interested in studying mesoscale quantum dynamics which arises when long length-scale process is coupled to a microscopic degree of freedom with quantum behavior. Mesoscale quantum dynamics can arise due to multi-particle interactions or material heterogeneities. Simulating these dynamics is challenging due to the massive number of pigments involved. We both develop new computational tools to tackle mesoscale quantum simulations and develop models for specific materials of interest - often in collaboration with experimental groups from around the world.
We have recently developed a quantum dynamics algorithm that is formally exact and has size invariant (i.e. O(1)) scaling. We are excited to develop this tool further and apply it to a broad range of chemical and material systems which have resisted theoretical efforts to date.