Reflections on Nano and Femto Imaging
Scanning near-field optical microscopy combined with pump–probe spectroscopy can resolve ultrafast dynamics at the nanoscale.
In this short article, Hrvoje Petek reflects on a new technique that combines the nanometre resolution of near-field microscopy with the femtosecond resolution of pump–probe spectroscopy. This technique has been developed by Markus Raschke and colleagues at the University of Colorado at Boulder and submitted in the present issue of Nature Nanotechnology.
“Imaging quantum phenomena in the femto–nano regime is a goal being pursued by physicists and chemists using various methods, all with their advantages and disadvantages”, writes Petek, who then proceeds to describe the various tradeoffs of several imaging techniques.
Petek then reports the new stratagem employed by Markus Raschke and colleagues to probe the coherent electron dynamics in a nanostructured gold film.
“In the future”, Petek concludes, “this ultrafast, nanoscale four-wave mixing imaging set-up can potentially be used to study the coherent dynamics of electronic and vibrational excitations in samples such as single molecules interacting with a solid or liquid environment, or coupling of excitons and plasmons in semiconductor and metallic nanoparticles.”
Read the full article in Nature Nanotechnology.