Controlled Switching of Néel Caps in Flux-Closure Magnetic Dots

Controlled switching of Néel caps in flux-closure magnetic dots.

While magnetic hysteresis usually considers magnetic domains, the switching of the core of magnetic vortices has recently become an active topic. We considered Bloch domain walls, which are known to display at the surface of thin films flux-closure features called Néel caps. We demonstrated the controlled switching of these caps under a magnetic field, occurring via the propagation of a surface...

Asymmetric hysteresis of Néel caps in flux-closure magnetic dots

We investigated with XMCD-PEEM magnetic imaging the magnetization reversal processes of Néel caps inside Bloch walls in self-assembled, micron-sized Fe(110) dots with fluxclosure magnetic state. In most cases the magnetic-dependent processes are symmetric in field, as expected. However, some dots show pronounced asymmetric behaviors. Micromagnetic simulations suggest that the geometrical featur...

Auroral streamers and magnetic flux closure

[1] On 7 December 2000 at 2200 UT an auroral streamer was observed to develop above Scandinavia with the IMAGE-FUV global imagers. The ionospheric equivalent current deduced from the MIRACLE-IMAGE Scandinavian ground-based network of magnetometers is typical of a substorm-time streamer. Observations of the proton aurora using the SI12 imager onboard the IMAGE satellite are combined with measure...

Self-assembly and flux closure studies of magnetic nanoparticle rings

Transformer inrush current mitigation using controlled switching and magnetic flux shunts

The inrush current is a transient current that results from a sudden change in the exciting voltage across a transformer’s windings. It may cause inadvertent operation of the protective relay system and necessitate strengthening of the transformer’s mechanical structure. Many methods were reported in the literatures for reduction and mitigation of transformer inrush currents. This paper represe...