Physics Colloquium: Mapping Chemistry, Composition, and Dynamics with Coherent Raman Imaging
Tuesday, September 12 at 3:15pm
Regents Hall, 109 3700 O St. NW
Marcus T. Cicerone, Ph.D.
National Institutes of Standards and Technology
Spectroscopic coherent Raman imaging (CRI) methods are opening up many exciting possibilities for understanding phenomena in biology and materials science.1 I will briefly introduce spectroscopic CRI, discussing some of the key concepts that make these methods practical. I will also present selected examples where we have investigated biological mechanisms and characterized materials through CRI with chemical contrast. I will additionally discuss possibilities for a contrast mechanism based on materials dynamics. Recent advances in our understanding of collective motion in non-crystalline condensed matter systems allows us to predict dynamic properties of these systems over 12 orders of magnitude in time with just a few parameters derived from picosecond timescale measurements.2 We expect these relationships to hold for a wide range of systems, including simple liquids, synthetic polymers and proteins. I will show that coherent Raman techniques can provide the parameters needed to predict dynamic properties, suggesting the possibility of spatially mapping dynamics in a molecularly specific way at optical resolution. CRI methods are beginning to prove valuable in a number of arenas; I anticipate that their use will become increasingly widespread as their potential is more fully explored and developed.
1. CH Camp and MT Cicerone, Chemically Sensitive Bioimaging with Coherent Raman Scattering, Nat. Photonics, 9, 295-305 (2015)
2. MT Cicerone, Qin Zhong and Madhusudan Tyagi, Picosecond Dynamic Heterogeneity, Hopping, and Johari-Goldstein Relaxation in Glass-Forming Liquids, Phys. Rev. Lett. 113, 117801 (2014)
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