Magnetic properties of single nanomagnets: Electron energy-loss magnetic chiral dichroism on FePt nanoparticles

Sebastian Schneider; Darius Pohl; Stefan Löffler; Ján Rusz; Deepa Kasinathan; Peter Schattschneider; Ludwig Schultz; Bernd Rellinghaus

doi:10.1016/j.ultramic.2016.09.009

Magnetic properties of single nanomagnets: Electron energy-loss magnetic chiral dichroism on FePt nanoparticles

Ultramicroscopy. 2016 Dec:171:186-194. doi: 10.1016/j.ultramic.2016.09.009. Epub 2016 Sep 20.

Authors

Sebastian Schneider¹, Darius Pohl², Stefan Löffler³, Ján Rusz⁴, Deepa Kasinathan⁵, Peter Schattschneider⁶, Ludwig Schultz⁷, Bernd Rellinghaus²

Affiliations

¹ IFW Dresden, Institute for Metallic Materials, PO Box 270116, D-01171 Dresden, Germany; TU Dresden, Institut für Festkörperphysik, D-01062 Dresden, Germany. Electronic address: [email protected].
² IFW Dresden, Institute for Metallic Materials, PO Box 270116, D-01171 Dresden, Germany.
³ TU Wien, University Service Centre for Electron Microscopy, Wiedner Hauptstraße 8-10, A-1040 Vienna, Austria; McMaster University, Department of Materials Science and Engineering, 1280 Main Street West, Hamilton, Ontario, Canada L8S4L8.
⁴ Uppsala University, Department of Physics and Astronomy, PO Box 516, S-75120 Uppsala, Sweden.
⁵ Max-Planck-Institut für Chemische Physik fester Stoffe, Department of Physics of Correlated Matter, Nöthnitzer Straße 40, D-01187 Dresden, Germany.
⁶ TU Wien, University Service Centre for Electron Microscopy, Wiedner Hauptstraße 8-10, A-1040 Vienna, Austria; TU Wien, Institute of Solid State Physics, Wiedner Hauptstraße 8-10, A-1040 Vienna, Austria.
⁷ IFW Dresden, Institute for Metallic Materials, PO Box 270116, D-01171 Dresden, Germany; TU Dresden, Institut für Festkörperphysik, D-01062 Dresden, Germany.

PMID: 27694036
DOI: 10.1016/j.ultramic.2016.09.009

Abstract

Electron energy-loss magnetic chiral dichroism (EMCD) allows for the quantification of magnetic properties of materials at the nanometer scale. It is shown that with the support of simulations that help to identify the optimal conditions for a successful experiment and upon implementing measurement routines that effectively reduce the noise floor, EMCD measurements can be pushed towards quantitative magnetic measurements even on individual nanoparticles. With this approach, the ratio of orbital to spin magnetic moments for the Fe atoms in a single L1₀ ordered FePt nanoparticle is determined to be m_l/m_s=0.08±0.02. This finding is in good quantitative agreement with the results of XMCD ensemble measurements.

Keywords: EMCD; L1(0) ordered FePt nanoparticles; Ratio of orbital to spin magnetic moment.

Publication types

Research Support, Non-U.S. Gov't