Magnetization reversal process in submicron epitaxial (10?0) Co dot arrays

摘要

Epitaxial arrays of (10?0) Co circular dots withdiameters of 0.3 #mu#m and 2.0 #mu#m were prepared byelectron-beam lithography and Ar ion etching. Magnetizationreversal processes influenced by well-defined magnetocrystallineanisotropy were examined with a magnetic force microscope(MFM) and a vector SQUID magnetometer. The coercive forceof both dot arrays is lower than that of an epitaxial Co film. FromMFM and vector magnetization measurements, a magneticvortex-like structure was found to be formed during thedemagnetization process for a 0.3 #mu#m circular dot array. Incontrast, a symmetrical domain structure was formed during thedemagnetization process for a 2.0 #mu#m dot array.