Magnetic antivortex-core reversal by circular-rotational spin currents.

Comment on "three-dimensional, spin-resolved structure of magnetic vortex and antivortex states in patterned co films using scanning ion microscopy with polarization analysis".

Scanning ion microscopy with polarization analysis is utilized for three-dimensional spin mapping of the surface magnetization (SM) of circular Co dots created in situ by focused ion beam etching of 30 nm thin Co/Si(100) films. From 3D scanning ion microscopy with polarization analysis spin maps, direct evidence is found for the existence of vortex-antivortex states with in-plane circular or hy...

Magnetic vortex-antivortex crystals generated by spin-polarized current

We study vortex pattern formation in thin ferromagnetic films under the action of strong spin-polarized currents. Considering the currents which are polarized along the normal of the film plane, we determine the critical current above which the film goes to a saturated state with all magnetic moments being perpendicular to the film plane. We show that stable square vortex-antivortex superlattic...

Magnetization reversal assisted by half antivortex states in nanostructured circular cobalt disks

Dynamic switching of the spin circulation in tapered magnetic nanodisks.

Magnetic vortices are characterized by the sense of in-plane magnetization circulation and by the polarity of the vortex core. With each having two possible states, there are four possible stable magnetization configurations that can be utilized for a multibit memory cell. Dynamic control of vortex core polarity has been demonstrated using both alternating and pulsed magnetic fields and current...

Microscopic realization of two-dimensional bosonic topological insulators.

It is well known that a bosonic Mott insulator can be realized by condensing vortices of a boson condensate. Usually, a vortex becomes an antivortex (and vice versa) under time reversal symmetry, and the condensation of vortices results in a trivial Mott insulator. However, if each vortex or antivortex interacts with a spin trapped at its core, the time reversal transformation of the composite ...