title: A new reversal mode in exchange coupled antiferromagnetic/ferromagnetic disks: distorted viscous vortex.
abstract: Magnetic vortices have generated intense interest in recent years due to their unique reversal mechanisms, fascinating topological properties, and exciting potential applications. In addition, the exchange coupling of magnetic vortices to antiferromagnets has also been shown to lead to a range of novel phenomena and functionalities. Here we report a new magnetization reversal mode of magnetic vortices in exchange coupled Ir20Mn80/Fe20Ni80 microdots: distorted viscous vortex reversal. In contrast to the previously known or proposed reversal modes, the vortex is distorted close to the interface and viscously dragged due to the uncompensated spins of a thin antiferromagnet, which leads to unexpected asymmetries in the annihilation and nucleation fields. These results provide a deeper understanding of the physics of exchange coupled vortices and may also have important implications for applications involving exchange coupled nanostructures.
authors.affiliation: Physics Department, University of California, Davis, CA, USA. kailiu@ucdavis.edu.
authors.forename: Dustin A
authors.initials: DA
authors.lastname: Gilbert
authors.forename: Li
authors.initials: L
authors.lastname: Ye
authors.forename: Aïda
authors.initials: A
authors.lastname: Varea
authors.forename: Sebastià
authors.initials: S
authors.lastname: Agramunt-Puig
authors.forename: Nuria
authors.initials: N
authors.lastname: del Valle
authors.forename: Carles
authors.initials: C
authors.lastname: Navau
authors.forename: José Francisco
authors.initials: JF
authors.lastname: López-Barbera
authors.forename: Kristen S
authors.initials: KS
authors.lastname: Buchanan
authors.forename: Axel
authors.initials: A
authors.lastname: Hoffmann
authors.forename: Alvar
authors.initials: A
authors.lastname: Sánchez
authors.forename: Jordi
authors.initials: J
authors.lastname: Sort
authors.forename: Kai
authors.initials: K
authors.lastname: Liu
authors.forename: Josep
authors.initials: J
authors.lastname: Nogués