Micromagnetic structures of recorded transitions in isotropic high-coercivity longitudinal thin films

A study of the micromagnetic structures of recorded transitions in isotropic longitudinal CoCr/sub 12/Ta/sub 2//Cr thin films with coercivities between 240 and 1410 Oe is made directly through the Cr underlayer using Fresnel Lorentz transmission electron microscopy (FLTEM). Fourier transforms of digitized magnetic images are used to quantify the micromagnetic structures of the recorded transitions which are found to be dominated by magnetic vortex structures. Adjacent vortices are found to have alternating directions of magnetization rotation in contrast to zigzag or sawtooth transitions observed in conventional uniaxial thin film recording media with average transition lengths of 1.2 to 0.6 mu m.>