title: Propagation of magnetic vortices using nanocontacts as tunable attractors.
abstract: Magnetic vortices in thin films are in-plane spiral spin configurations with a core in which the magnetization twists out of the film plane. Vortices result from the competition between atomic-scale exchange forces and long-range dipolar interactions. They are often the ground state of magnetic dots, and have applications in medicine, microwave generation and information storage. The compact nature of the vortex core, which is 10-20 nm wide, makes it a suitable probe of magnetism at the nanoscale. However, thus far the positioning of a vortex has been possible only in confined structures, which prevents its transport over large distances. Here we show that vortices can be propagated in an unconstrained system that comprises electrical nanocontacts (NCs). The NCs are used as tunable vortex attractors in a manner that resembles the propelling of space craft with gravitational slingshots. By passing current from the NCs to a ferromagnetic film, circulating magnetic fields are generated, which nucleate the vortex and create a potential well for it. The current becomes spin polarized in the film, and thereby drives the vortex into gyration through spin-transfer torques. The vortex can be guided from one NC to another by tuning attractive strengths of the NCs. We anticipate that NC networks may be used as multiterminal sources of vortices and spin waves (as well as heat, spin and charge flows) to sense the fundamental interactions between physical objects and fluxes of the next-generation spintronic devices.
authors: 1] IMEC, Kapeldreef 75, B-3001 Leuven, Belgium [2] Laboratorium voor Vaste-Stoffysica en Magnetisme, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, B-3001 Leuven, Belgium.
authors: M
authors: M
authors: Manfrini
authors: 1] Institut d'Electronique Fondamentale, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8622, 91405 Orsay, France [2] Université Paris-Sud, 91405 Orsay, France.
authors: Joo-Von
authors: 000000023849649X
authors: JV
authors: Kim
authors: 1] Institut d'Electronique Fondamentale, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8622, 91405 Orsay, France [2] Université Paris-Sud, 91405 Orsay, France [3].
authors: S
authors: S
authors: Petit-Watelot
authors: IMEC, Kapeldreef 75, B-3001 Leuven, Belgium.
authors: W
authors: W
authors: Van Roy
authors: 1] IMEC, Kapeldreef 75, B-3001 Leuven, Belgium [2] Laboratorium voor Vaste-Stoffysica en Magnetisme, Katholieke Universiteit Leuven, Celestijnenlaan 200 D, B-3001 Leuven, Belgium.
authors: L
authors: L
authors: Lagae
authors: 1] Institut d'Electronique Fondamentale, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8622, 91405 Orsay, France [2] Université Paris-Sud, 91405 Orsay, France.
authors: C
authors: C
authors: Chappert
authors: 1] Institut d'Electronique Fondamentale, Centre National de la Recherche Scientifique, Unité Mixte de Recherche 8622, 91405 Orsay, France [2] Université Paris-Sud, 91405 Orsay, France.
authors: T
authors: T
authors: Devolder