ANISOTROPIES, CONE STATES, AND STRIPE DOMAINS IN CO PT MULTILAYERS/

We present results for perpendicular uniaxial anisotropies obtained us ing torque magnetometry and magnetic force microscopy on epitaxially g rown Co/Pt multilayers. A strong dependence of the two lowest order un iaxial anisotropies on Pt film thickness and temperature were observed . The possibility of an interfacial strain origin for the anisotropies due to lattice mismatch between the Co and Pt is discussed. A surpris ing result is the appearance of magnetic orientations at oblique angle s with respect to the film plane and the surface normal. These orienta tions are identified as ''cone states'' and found to exist in limited ranges of Pt film thickness and temperatures. The temperature dependen ce is very unusual and controlled through the behavior of the lowest o rder perpendicular uniaxial anisotropies. The magnetization process wa s also examined in terms of saturation fields and domain formation. Na rrow stripe domains with periods less than 100 nm were observed in the demagnetized state using magnetic force magnetometry and multilayer e ffects on the domain period and associated saturation fields were foun ds. (C) 1997 American Institute of Physics.