Influence of eddy currents on reversal processes in nanocubes depending on size

The effect of eddy currents on reversal processes in Permalloy nanocubes has been studied. Three different behaviors have been found in the size range covered (8 nm-40 nm). The magnetization of small nanocubes rotate quasicoherently and the effect of eddy currents is found to be negligible. For the largest nanocubes evaluated the reversal process is achieved by means of a curling-like process. In this case, the effect of eddy currents favors the magnetization curling and triggers the reversal reducing the switching time. For the intermediate size, (L=32 nm), a different behavior is found. The magnetization is trapped in a vortex-like state, and the switching takes place in three stages. Eddy currents speed up vortex formation whereas they delay the complete reversal.