Studies of the Magnetization Reversal Processes in Co Dot and AntidotArrays on a Microscopic Scale

摘要

Co dot and antidot arrays with hexagonal symmetry have been prepared by combined electrochemical andsputtering techniques with significantly reduced nanoscale dimensions. Their magnetization reversal process has beenanalyzed on a macroscopic scale with Vibrating Sample Magnetometry (VSM) and on a microscopic scale by high spatialresolution Magnetic Transmission Soft X-ray Microscopy (MTXM). We observe for the antidot arrays a nucleation andpropagation mode driven reversal mechanism induced by the in-plane anisotropy starting with nucleated clustersfollowing the hexagonal configuration, and the magnetic hardness (i.e., coercivity) depending on the geometryparameters. Contrary, for arrays of short dots, a significant longitudinal anisotropy is deduced with large coercivity, wheremagnetostatic interactions gives rise to a more complex reversal process and significantly reduced remanence andsusceptibility.