The new paradigm of electron microscopy – on the way to the ultimate limits of optics

Mittwoch, 27. Februar, 9:15 Uhr, H 0105

Seventy years after its invention by Ernst Ruska (Nobel laureate 1987) transmission electron microscopy has entered a dramatic phase of development and has set out to quest for the ultimate limits of microscopies. The key to this is the recent introduction of aberrationcorrected electron optics opening up the way to atomic-resolution electron microscopy in the sub-Angström range. Since the images obtained this way are based on quantum physics their content can only be understood quantitatively on the basis of a comparison with proper solutions of the Schrödinger equation. This way novel investigations on defect structures e.g. in oxides, superconductors and ferroelectrics have become possible in which one not only can determine the local oxygen content on the atomic level but also one can measure atomic displacements at an accuracy of a few picometers. Furthermore instruments equipped with electron monochromators and spectrometers allow to study and measure related electron states at an energy resolution better than 100 meV. The lecture will provide an introduction to this exciting field and elaborate on the foreseeable limits given by the width of the electron wave function.

Knut Urban
Institute for Solid State Research and Ernst Ruska Centre for Microscopy and Spectroscopy with Electrons, Helmholtz Research Centre Jülich, and Chair for Experimental Physics IVE, RWTH Aachen University