Magnetic torque behavior and rotational hysteresis of amorphous uniaxial Sm-Co alloy films

Amorphous films of Sm_100–x Co _x with 70x90 were made by vapor deposition on flat glass substrates at 300 K with a magnetic field parallel to the film plane, as described in a preceding paper; the field induces a uniaxial anisotropyK _u of the order 10⁶ erg cm^–3 with the easy axis,x, in the film plane. The film plane (xy plane) is the easy plane with a planar anisotropyK _p of the order 10⁷ erg cm^–3, i.e. the film normal,z, is the hard axis. For such films, torque curvesT(H, ) (: angle betweenH and an axis normal to the axis of rotation) are calculated, and are measured in fieldsH 30 kOe for the three axes of rotation,x, y, andz. The results are evaluated to give the spontaneous magnetization, M, the anisotropies,K _u ,K _p , the rotational hysteresis losses,W _Rx (H),W _Ry (H),W _Rz (H), and the rotational hysteresis integrals,R _x ,R _y ,R _z .