Field angle dependent change of the magnetization reversal mode in epitaxial Co (0001) films

Control of domain structure and magnetization reversal in thick Co/Pt multilayers

“…In contrast to this change in the nucleation behavior, the central hysteresis band does not disappear, but instead increases. Analogous to the situation earlier observed in thick (0001) oriented Co-films[12,13], the angular extension of the nucleation process is controlled by the evolution of the μ0Hcr (β) and μ0Hn (β) curves and by their complete different angular dependence that produces a crossing at a specific β. By reducing the ratio between anisotropy and magnetostatic 7 energy in favor of the latter, which was achieved for instance in Ref.13 by increasing the temperature of pure single Co films, the angular position of the crossing point shifts towards β = 0° until its complete suppression.…”

“…Upon changing β away from the OOP orientation, the width of these regions in field gradually reduces, and they completely disappear for β > 10° or β < -10°. Hence we can conclude that for orientation β > 10° and β < -10° the magnetization reverses by undergoing a second-order rather than a first-order phase transition[12,13]. On the contrary, the color-coded map for N = 8(Fig.…”

“…Magnetic thin films with competing long and short-range interactions are a very important research topic in the field of ferromagnetism [1,2]. Due to their close competition, complex magnetization reversal processes as well as spatially inhomogeneous magnetic multi-domain states generally occur [3][4][5][6][7][8][9][10][11][12][13]. Undoubtedly, artificial layered structures consisting of alternating ferromagnetic (FM) / non-magnetic layers rightfully belong to this category [14][15][16][17][18].…”

“…The majority of these studies, though, utilized very thin FM layers, since an in-plane magnetization reorientation is expected for thicker films [47,[53][54][55]. However, for sufficiently thick FM layers and in the presence of out-of-plane crystalline magnetic anisotropy, it was found that the magnetization undergoes a second reorientation transition back to out-of-plane orientation [6,12,13,30,56,57].…”

“…. 3, our multilayer samples show fundamentally different magnetization reversal processes while applying the magnetic field along in-and out-of-plane directions and by varying N. As a result, in order to fully magnetically characterize this kind of system, not only IP and OOP orientations of the magnetic field should be explored, but also any intermediate field angles.In order to perform this angular dependent study, a convenient methodology introduced in earlier studies was utilized[12,13], which takes advantage of the normalized magnetization difference ΔM/MS between the ascending and descending branches of the magnetization curves.Correspondingly, M(H) curves have been measured for different applied field orientations 5 β, in steps of Δβ = 5° for 30° ≤ β ≤ 95°, and Δβ = 2° for -30° ≤ β ≤ 28°. The complete angular dependence of the normalized magnetization difference is shown inFig.…”