First-principles theory of chiral dichroism in electron microscopy applied to 3d ferromagnets

Abstract

First-principles theory of chiral dichroism in electron microscopy applied to 3d ferromagnets

Ján Rusz Institute of Physics, Academy of Sciences of the Czech Republic, Cukrovarnická 10, 162 53 Prague 6, Czech Republic and Department of Physics, Uppsala University, Box 530, S-751 21 Uppsala, Sweden

Stefano Rubino Institute for Solid State Physics, Vienna University of Technology, Wiedner Hauptstrasse 8-10/138, A-1040 Vienna, Austria

Peter Schattschneider Institute for Solid State Physics, Vienna University of Technology, Wiedner Hauptstrasse 8-10/138, A-1040 Vienna, Austria and University Service Centre for Electron Microscopy, Vienna University of Technology, A-1040 Vienna, Austria

Recently it was demonstrated [Schattschneider et al., Nature 441, 486 (2006)], that an analog of the x-ray magnetic circular dichroism experiment can be performed with the transmission electron microscope. The new phenomenon has been named energy-loss magnetic chiral dichroism. In this work we present a detailed ab initio study of the chiral dichroism in the Fe, Co, and Ni transition elements. We discuss the methods used for the simulations together with the validity and accuracy of the treatment, which, in principle, can apply to any given crystalline specimen. The dependence of the dichroic signal on the sample thickness, accuracy of the detector position, and the size of convergence and collection angles are calculated.