In-plane magnetoresistance and magnetization reversal of cobalt antidot arrays Available to Purchase

Cobalt antidot arrays defined within a Hall bar mesa have been fabricated using electron-beam lithography. The diameter of the circular antidots was fixed at $1μm$ with the antidot edge-to-edge spacing varying from $2to0.5μm$ in a square lattice and $0.4μm$ in a rotated square lattice. In-plane magnetoresistance measurements were carried out to investigate the magnetization reversal properties. Antidots greatly modify the domain configuration and work as domain wall pinning sites. As a result, the switching and saturation fields increase while the magnetoresistance ratio decreases with the inclusion of antidots and also with increasing antidot areal density. Micromagnetic simulations show that the magnetization reversal of antidot arrays proceeds with the formation and annihilation of domain walls, which is manifested as Barkhausen jumps in the transition regions of the magnetoresistance curves.