Graham R. Fleming
University of California, Berkeley
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Primary Section: 14, Chemistry Secondary Section: 29, Biophysics and Computational Biology Membership Type:
Member
(elected 2007)
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Research Interests
My research focuses on developing an understanding of condensed phase dynamics with applications to chemistry, biophysics and condensed matter physics. To this end, my laboratory combines ultrafast spectroscopy, analytical theory and simulation. The primary steps of photosynthesis - light harvesting, and electron transfer - are topics of particular interest. We have discovered many of the design principles used to optimize and regulate photosynthetic light harvesting, including most recently the role of quantum coherence in enhancing efficiency. We have also characterized the timescales and molecular mechanism by which water and other highly polar liquids accommodate to changes in electronic structure of solute, and shown that chemically reactive motion in solution is often free, ballistic motion (rather than diffusive) over chemically significant length scales and for chemically significant timescales. New nanoscale materials may have electronic structures that are described neither by infinite semiconductor approaches or molecular approaches. Single-walled carbon nanotubes are one such example and my laboratory showed that an excitonic description is required, determined the exciton binding energy, and has recently shown that electronic coherence is extraordinarily long-lived - even at room temperature - in these systems. Our work often depends on the development of new non-linear optical techniques and examples include fluorescence interferometry, new classes of photon echo spectroscopy and two-dimensional electronic and Raman spectroscopy.
