nn9b07448_si_001.pdf (1.01 MB)
Exotic Transverse-Vortex Magnetic Configurations in CoNi Nanowires
journal contribution
posted on 2019-12-13, 18:06 authored by Ingrid Marie Andersen, Luis Alfredo Rodríguez, Cristina Bran, Cécile Marcelot, Sébastien Joulie, Teresa Hungria, Manuel Vazquez, Christophe Gatel, Etienne SnoeckThe magnetic configurations of cylindrical Co-rich CoNi
nanowires
have been quantitatively analyzed at the nanoscale by electron holography
and correlated to local structural and chemical properties. The nanowires
display grains of both face-centered cubic (fcc) and hexagonal close
packed (hcp) crystal structures, with grain boundaries parallel to
the nanowire axis direction. Electron holography evidences the existence
of a complex exotic magnetic configuration characterized by two distinctly
different types of magnetic configurations within a single nanowire:
an array of periodical vortices separating small transverse domains
in hcp-rich regions with perpendicular easy axis orientation and a
mostly axial configuration parallel to the nanowire axis in regions
with fcc grains. These vastly different domains are found to be caused
by local variations in the chemical composition modifying the crystalline
orientation and/or structure, which give rise to change in magnetic
anisotropies. Micromagnetic simulations, including the structural
properties that have been experimentally determined, allow for a deeper
understanding of the complex magnetic states observed by electron
holography.