MAGNETORESISTANCE AND KERR EFFECT INVESTIGATIONS OF CO CU MULTILAYERSWITH WEDGE-SHAPED CU LAYERS/

The magnetic coupling behaviour of dc-magnetron sputtered Co/Cu multil ayers with wedge shaped Cu interlayers was investigated by magnetoresi stance (MR). The well known oscillatory behaviour of both the amplitud e of the MR effect and the saturation field H(s) was found. Within the first region of antiferromagnetic coupling around 1 nm Cu there is a different thickness dependence of H(s) and MR presumably caused due to the imperfect structure of our multilayer System. Domain nucleation a nd reversal behaviour were studied by Kerr microscopy and correlated w ith the observed coupling states determined by MR. There were no clear hints for a biquadratic coupling term.