[Aspuru-Guzik group list] TODAY: Excitonics Seminar - Professor Ian Mercer - September 29

Center for Excitonics Seminar Series Announcement The Center for Excitonics (http://www.rle.mit.edu/excitonics) invites you to join us at the first seminar of the Fall 2009 series. Please forward this information on to others who might be interested in attending this seminar. Title: Quantum Dimension of Photosynthesis Revealed by Angular Resolved Coherent Imaging Presenter: Professor Ian Mercer Organization: Department of Physics, University College Dublin Date: September 29, 2009 Time: 3:00 - 4:00pm Place: 36-428 Refreshments: Yes URL: http://www.rle.mit.edu/excitonics/mercer-092909.html abstract Understanding the role of coherent electronic motion is expected to resolve general questions of importance in macromolecular energy transfer, in nature and in devices. Significant progress has been made using coherent optical four wave-mixing, however the interpretation of measurements is difficult in particular where multiple quantum transitions are strongly coupled, and new methods are required for an improved feedback to molecular simulation. We will look at a novel laser method, Angle-Resolved Coherent (ARC) imaging, that separates quantum coherences from energy transfers in to orthogonal dimensions, in an instantaneous two-dimensional mapping. The power of the new method is demonstrated with the light harvesting complex II (LH2) of purple bacteria. We reveal an evolving quantum coherence with a time-ordered matter-selection of transition energies at ambient temperature. We also reveal a coherent component to the energy transfer between macromolecular rings and a correlation between excitation and emission energies within a ring at ambient temperature. bio Ian Mercer is currently lecturing in Physics at University College Dublin in Ireland. He has previous experience as a laser company CTO (UK), a lecturer in Chemistry at Imperial College (UK) and a PI and Team Leader at LLNL (US). His has interests in combining new laser methods, laser technology and molecular-optical simulation for revealing biomolecular and electronic device function. energies within a ring at ambient temperature.