Nanoscale switch for vortex polarization mediated by Bloch core formation in magnetic hybrid systems

Schematic diagram of vortex core reversal process. The vortex core magnetisation reverses its orientation when crossing a domain boundary (black down arrow to white up arrow).

Vortices are fundamental magnetic topological structures characterized by a curling magnetization around a highly stable nanometric core. The control of the polarization of this core and its gyration is key to the utilization of vortices in technological applications. So far polarization control has been achieved in single-material structures using magnetic fields, spin-polarized currents or spin waves. Here we demonstrate local control of the vortex core orientation in hybrid structures where the vortex in an in-plane Permalloy film coexists with out-of-plane maze domains in a Co/Pd multilayer. The vortex core reverses its polarization on crossing a maze domain boundary. This reversal is mediated by a pair of magnetic singularities, known as Bloch points, and leads to the transient formation of a three-dimensional magnetization structure: a Bloch core. The interaction between vortex and domain wall thus acts as a nanoscale switch for the vortex core polarization.

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https://youtu.be/sdDjS6KMQLQ
Original Publication
Nanoscale switch for vortex polarization mediated by Bloch core formation in magnetic hybrid systems
P. Wohlhüter, M. T. Bryan, P. Warnicke, S. Gliga, S. E. Stevenson, G. Heldt, L. Saharan, A. K. Suszka, C. Moutafis, R. V. Chopdekar, J. Raabe, T. Thomson, G. Hrkac and L. J. Heyderman
Nature Communications 6, Article number: 7836,Published 4 Aug 2015, DOI: 10.1038/ncomms8836
Contact
Prof. Laura Heyderman
Laboratory for Mesoscopic Systems, Department of Materials, ETH Zurich
Laboratory for Micro- and Nanotechnology, Paul Scherrer Institute
5232 Villigen PSI; Switzerland
Phone: +41 56 310 2613, e-mail: laura.heyderman@psi.ch


Dr. Joerg Raabe, Swiss Light Source
Paul Scherrer Institut, 5232 Villigen PSI, Switzerland
Phone: +41 56 310 5193, e-mail: joerg.raabe@psi.ch