The soft magnetic properties of stripes fabricated using laser ablation of multilayer thin films

We examine the low frequency BH loop and complex permeability spectra of multilayer permalloy films laser processed to define samples consisting of stripes parallel to the as-deposited hard axis. We begin by examining different laser energy densities for groove definition in films of different thickness. We observe that for well coupled multilayer films with thin, 15 nm, spacer layers the demagnetizing field, which is a function of groove depth, is able to reorient the easy and hard axes from the initial orientation. As the groove becomes more clearly defined the hard axis permeability increases, while the easy axis permeability decreases. The role of stripe width and ambient processing atmosphere are also investigated.