May 15 – 20, 2022
Hotel Hermitage, La Biodola Bay, Elba Island, Italy
Europe/Rome timezone

Ferrimagnetic switching driven by stochastic resonance in multiferroic (Ge,Mn)Te

May 18, 2022, 6:00 PM
20m
Hotel Hermitage, La Biodola Bay, Elba Island, Italy

Hotel Hermitage, La Biodola Bay, Elba Island, Italy

Biodola Bay 57037 Portoferraio (LI) Isola d’Elba - Italy
Oral

Speaker

Juraj Krempasky

Description

The interplay between spin-orbit interaction (SOI) and magnetic order is currently one of the most active research fields in condensed matter physics. We report on ferrimagnetic switching driven by stochastic resonance in multiferroic (Ge,Mn)Te, investigated by x ray magnetic linear and circular dichroism (XMLD/XMCD), supported by SPR-KKR-CPA scattering and magnetic cluster calculations. In accordance with our previous resonant ARPES results, we find that the Mn-atoms occupy two distinct substitutional and interstitial lattice sites by substituting Ge-atoms. We show that (Ge,Mn)Te antiferromagnetically couples its Mn-sites with slightly different magnetic moments, resulting in a ferrimagnetic order. One of the astonishing results is that XMCD data show that the system spontaneously switches its magnetisation direction, without changing external parameters such as light helicity, applied B-fields or temperature (up to 65 K). The switching reveals ultra-slow magnetization dynamics, which can be governed by the stochastic resonance. Finally, we demonstrate that the occurrence of ferrimagnetic switching is closely related to the formation of topological spin textures in the films, enabled by the interplay of antiferromagnetic and Dzyaloshinskii-Moriya interactions.

Primary authors

Dr Carlos A.F. Vaz (Photon Science Division, Paul Scherrer Institut, Villigen, Switzerland) Prof. Gunther Springholz (Institut für Halbleiter-und Festkörperphysik, Johannes Kepler Universität, Linz, Austria) Prof. Jan Minar (New Technologies-Research Center, University of West Bohemia, Plzeň, Czech Republic) Juraj Krempasky Dr Cinthia Piamonteze (Photon Science Division, Paul Scherrer Institut, Villigen, Switzerland) Prof. Hugo Dil (Institute of Physics, Ecole Polytechnique Fédérale de Lausanne, Switzerland) Dr Martin Gmitra (Institute of Physics, Pavol Jozef Šafárik University in Košice, Slovakia) Dr Ondrej Caha (Masaryk University, Brno, Czech Republic) Dr Valerio Scagnoli (Mesoscopic Systems, ETH Zurich, Switzerland) Dr Wilfred Sunil (New Technologies-Research Center, University of West Bohemia, Plzeň, Czech Republic)

Presentation materials