The magnetization reversal in a sputtered ${\mathrm{Sm}}_{40}{\mathrm{Fe}}_{60}\left(88\mathrm{}\mathrm{nm}\right)/{\mathrm{Ni}}_{80}{\mathrm{Fe}}_{20}\left(62\mathrm{}\mathrm{nm}\right)$ hard/soft bilayer with induced uniaxial anisotropy was investigated by Kerr microscopy and magnetometry. In the reversible regime of the hysteresis loop a twisting of magnetization across the thickness of the soft magnetic film could be derived. The hard layer reverses by the nucleation and growth of regular domains. They are separated from the nonswitched areas by tilted domain walls, the angle of which can be predicted by considering the net magnetic moments of the bilayer system.

• Received 28 February 2002

DOI:https://doi.org/10.1103/PhysRevB.66.134409