Domains and magnetic reversals in CoCr

Magnetron sputtered CoCr layers with various thicknesses, coercivities and other magnetic properties have been studied by a digital enhanced magneto-optical Kerr microscope. The slope (T) at [dM/dH]M=φ is determined from the perpendicular hysteresis loop. Together with K1these values have been used for calculation of the characteristic stripe domain properties. The observed domain densities have been compared with the calculated densities based on a continuous or particular behaviour of CoCr. The relation between typical fields (like the nucleation field and surface coercivity), the observed domain configuration and the shoulder of the hysteresis loop are given. On the basis of the domain structure (from stripe to cluster-like) we conclude that the samples can be classified in low, medium and high coercive layers.