Study of magnetic easy axis 3D-arrangement in L10-CoPt(111)/Pt(111)/MgO(100) tilted system for perpendicular recording

Angular magnetic properties of high anisotropy L10 CoPt (111) films showing a tilted magnetic easy axis configuration without an oblique grains microstructure were studied investigating the field dependence of remanent magnetization while rotating the magnetic field inside three intersecting planes. The out-of-plane tilting of the L10 c-axis (the easy axis of the tetragonal cell) was induced using a Pt (111) underlayer deposited onto a single crystal MgO substrate in a conventional Pulsed Laser Deposition (PLD) frontal deposition. The observed behavior is consistent with the presence of four easy axes with mutually orthogonal in-plane projections, symmetrically tilted at 36° with respect to the film plane. Such system can be used, like a common single-axis tilted medium, to record information in perpendicular mode, lowering the writing field to approximately 75% of the value along the easy direction, still maintaining the high medium thermal stability typical of the L10 alloy. Moreover, the in-plane charge compensation arising from this easy axis arrangement when a perpendicular writing field is applied, may favor a media noise reduction and better performances with respect to a single-axis tilted system.