New insight into the fundamental physics of low - dimensional a nd self - assembled materials using electron microscopy

Datum

22.01.2013

Zeit

16:40 - 18:10

Sprecher

Prof. Dr. Rafal E. Dunin - Borkowski

Zugehörigkeit

Ernst Ruska - Centrefor Microscopyand Spectroscopywith Electrons Institutefor Microstructure Research, Research Centre Jülich

Serie

TUD Physikalisches Kolloquium

Sprache

en

Hauptthema

Physik

Andere Themen

Physik

Beschreibung

In this talk, I will present a selection of recent results obtained in both high - resolution and Lorentz modes from a recently installed Titan Ultimate field emission gun transmission electron microscope equipped with a combined spherical and ch romatic aberration corrector on the objective lens. I will show how such studies can be used to obtain unique information about the fundamental physical properties of low - dimensional materials, including graphene, as well as to measure the local magnetic p roperties of self - assembled materials, including arrays of closely - spaced sub - 10 - nm ferromagnetic nanoparticles. Transmission electron microscopy has been revolutionised in recent years, both by the introduction of new hardware such as field - emission electron guns, aberration correctors, monochromators, imaging filters and in situ stages and by the development of new techniques, algorithms and software. Chromatic aberration correction, in particular, promises to provide improved spatial resolution and interpretability when compared with the use of spheri cal aberration correction alone, especially at lower accelerating voltages. It also promises to allow magnetic information about materials to be recorded with a spatial resolution of better than 0.5 nm with the conventional microscope objective lens switch ed off. I will conclude with a personal perspective on directions for the future development of transmission electron microscopy. Such developments may ultimately lead to approaches for characterising the positions, chemical identities and magnetic moments of individual atoms in three dimensions.

Letztmalig verändert: 22.01.2013, 09:00:52