An introduction to optical scanning probe microscopies for sub-wavelength imaging is given. Application to metal nanoparticles and their unique nano-optical features are described. Particular attention is given to recent advances in our laboratories for imaging collective electronic (plasmonic) responses of metallic materials, and the resulting ramifications for next-generation spectroscopies and sensors.

Bio Sketch
Gary Wiederrecht earned a B.S. in Chemistry from UC Berkeley in 1987, a Ph.D. in Chemistry from MIT in 1992 and is currently a Scientist and Group Leader, Nanophotonics Group, Chemistry Division, Argonne National Laboratory. He is a Senior Fellow of the University of Chicago/Argonne National Laboratory Consortium for Nanoscience Research and Theme Leader, Nanophotonics, Center for Nanoscale Materials. In addition, he leads research directions on new optical and scanning probe microscopies of photonic and plasmonic materials, as well as time-resolved spectroscopies of photochemistry in nanostructured hybrid materials. Recently he co-developed plasmonic continuum spectroscopy using ultrafast optical pulses and also co-developed an optical signal processor with photorefractive liquid crystals (R&D 100 Award). Lastly, he received the Presidential Early Career Award for Scientists and Engineers (PECASE) and is a member of ACS and APS.