Abstract: Coherent Raman scattering (CRS) techniques are recognized for their ability to induce and detect vibrational coherences in molecular samples. The generation of coherent light fields in CRS produces much stronger signals than what is common in incoherent Raman spectroscopy, while also enabling direct views of evolving molecular vibrations. Despite the attractive attributes of CRS spectroscopy, the technique’s sensitivity is insufficient for performing measurements on single molecules, thus precluding the ability to coherently drive, manipulate and observe individual vibrational quantum oscillators with light. The single-molecule sensitivity that has been achieved in surface-enhanced Raman scattering (SERS) with the aid of plasmonic antennas suggests that a similar approach may be used to push CRS techniques to the single-molecule detection limit. Compared with SERS, however, experimental successes in surface-enhanced coherent Raman scattering (SE-CRS) are few, and a theoretical understanding of surface-enhancement in CRS is still incomplete. In this lecture, we discuss some of the principles and challenges in SE-CRS and summarize the latest advances in the quest of performing routine CRS experiments on single molecules.
About the Speaker: Eric Potma earned his master's at the University of Groningen in 1996, where he also received his PhD in 2001. While working in the ultrafast spectroscopy group of Prof. Douwe Wiersma, Eric focused his research on the development of laser sources for microscopy and the application of nonlinear methods to optical imaging. In 2001, Potma joined the group of Prof. Sunney Xie at Harvard University as a postdoctoral fellow. During this time, he was been involved with projects on synchronizing mode-locked lasers, visualizing lipid bilayers with coherent Raman scattering microscopy and vibrational imaging of tissue in vivo at video rate. In 2005, Eric joined the Department of Chemistry at the University of California, Irvine where he is currently a professor of chemistry. His group focuses on the characterization of nano-structured materials and biological tissues with the aid of new optical imaging techniques.
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