Magnetization processes in ferromagnetic nanostructures with competing anisotropies

Surface-induced anisotropy and multiple states in elongated magnetic nanoparticles

“…[9][10][11] Because the strengths of these anisotropy contributions and the relative orientation of the easy axes can vary over a broad range, the system should possess a large variety of magnetic phases with different types of spontaneous and induced magnetic reorientation transitions. [9][10][11] Because the strengths of these anisotropy contributions and the relative orientation of the easy axes can vary over a broad range, the system should possess a large variety of magnetic phases with different types of spontaneous and induced magnetic reorientation transitions.…”

Phenomenological theory of magnetization reversal in nanosystems with competing anisotropies

“…Generally model ( 9) describes magnetic states in a planar ferromagnet with competing uniaxial (second-order) and biaxial (fourth-order) magnetic anisotropy. The model has been applied for many bulk and nanoscale magnetic systems, including reorientation effects in rare-earth orthoferrites [42,49], several classes of intermetallic compounds [50], first-order magnetization processes in highanisotropy materials [38], and for magnetic nanolayers with surface/interface-induced magnetic anisotropy [3,4,8,39,40,46,47]. The model from Eq.…”

“…The phase diagrams of solutions in Figs. 1-4 can be applied for explanation of magnetization processes in many nanomagnetic systems with competing anisotropies, for example, in thin films of diluted magnetic semiconductors (DMS), in ferromagnetic(FM)/antiferromagnetic(AFM) bilayers [8,23], Heusler alloys [61], and/or nanoparticles [15,47]. First, we consider the phase diagrams with symmetric arrangement of easy uniaxial and cubic anisotropy axes (Fig.…”

“…In section II we introduce the phenomenological model and methods; in the next section we derive all possible magnetic configurations in the system, calculate their stability limits, and describe reorientation effects [42,47,48]. These results enable us to calculate the parameters of the multidomain states and analyse the magnetization processes (section IV).…”