Fractional vortices and composite domain walls in flat nanomagnets.
We provide a simple explanation of complex magnetic patterns observed in ferromagnetic nanostructures. To this end we identify elementary topological defects in the field of magnetization: ordinary vortices in the bulk and vortices with half-integer winding numbers confined to the edge. Domain walls found in experiments and numerical simulations in strips and rings are composite objects containing two or more of the elementary defects.
Tchernyshyov
Oleg
O
Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, Maryland 21218, USA.
Chern
Gia-Wei
GW