Stripe domains morphology versus layers thickness in CoPt multilayers

The domain morphology in CoPt multilayers has been investigated by means of magnetic force microscopy for a broad range of thickness parameters. Following hard-axis saturation, complex closure domains, isolated reversed domains, and segmented and fully developed stripe patterns are clearly identified down to stripe widths of the order of 50 nm. Pending full numerical simulations, the stripe width behavior versus Co and Pt thicknesses has been confronted to the predictions of a purely magnetostatic model. The data are consistent with the existence of a single and physically realistic characteristic length, which, however, is viewed as mostly casual. Likely reasons are discussed.