"Single atom and vibrational spectroscopies in the electron microscope"

Who: Ondrej L. Krivanek (Nion R&D, and Department of Physics, Arizona State University, Tempe, Arizona, USA)

Place: nanoGUNE seminar room, Tolosa Hiribidea 76, Donostia - San Sebastian

Date: Friday, 29 September 2017, 11:00

Modern-day electron microscopes are able to form intense electron probes as small as 0.5-1 in diameter, or slightly larger probes that have an energy spread <10 meV.  This allows them to analyze single atoms spectroscopically (by electron energy loss spectroscopy (EELS) or energy-dispersive X-ray spectroscopy (EDXS)), and to probe the chemical composition of organic materials while avoiding radiation damage. 
Nion has pioneered many of these advances, by developing STEM aberration correction technology (in the 1990s), and then a new electron microscope that is able to acquire images and spectra from single atoms (in 2008, with continuing developments since), and which may make atom-by-atom materials engineering a practical reality.  We have also introduced a new type of a monochromator, which allows materials to be probed by vibrational EELS carried out with better than 10 meV energy resolution and about 1 nm spatial resolution, as well as damage-free vibrational analysis in an ?aloof? mode.   

My talk will review these advances and illustrate them with practical examples.

Host: Javier Aizpurua

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