Towards an efficient way of producing electron vortices in TEM
11 oktober 2013
University of Antwerp, Campus Groenenborger, X.009 - Groenenborgerlaan 171 - 2020 Antwerpen
12.30 - 13.30 uur
Organisatie / co-organisatie:
Electron microscopy for materials science
Friday Lectures Electron microscopy for materials science - Speaker: Armand Béché
Since their first creation a few years ago, interest in the production and use of electron vortex beams has grown to reach the ultimate goal of mapping magnetic information down to the atomic scale. However, the creation of an electron vortex beam of good quality, high purity, high intensity and atomic size faces several problems. One of the best solutions seems to rely on the use of the magnetic field produced at the tip of a magnetized needle. Shining an electron plane wave on the spiralling phase shift induced by the magnetic field will generate a vortex whose properties can be changed with the magnetic field. In this lecture, we will introduce electron vortices before reviewing the different ways of creating electron vortex beams. This will lead us to the description of the magnetic needle and its interesting capabilities of producing electron vortex beams.