A micromagnetic study of the hysteretic behavior of antidot Fe films

Scaling of the coercivity with the geometrical parameters in epitaxial Fe antidot arrays

“…Although some authors have proposed a tentative k scaling of the coercivity for antidots, both simulations and experimental data are not conclusive. 13,19 In fact, any physically meaning parameter scaling the coercivity must involve, in some way, both the separation k and the diameter D. Taking into account that one of the key issues of the magnetization processes of antidot arrays lies in the formation of highly stable, inhomogenous magnetization structures ("pinned regions") generated around the antidots, we have considered their relative area (with respect to the total Fe area of the array) as a scaling parameter. The characteristic length of magnetization inhomogeneities in iron is of the order of the domain wall width d, about 50 nm for Fe, 20 from which the relative size S of the pinned regions (inset in Fig.…”

A micromagnetic study of the reversal mechanism in permalloy antidot arrays

“…These results are in agreement with the ones found both experimentally and numerically in previous papers for a square lattice configuration. 5,7,14,16 In particular, the system obeys the well-known phenomenological linear relationship between the coercive field and the geometrical parameter 1/(p À h). 16 This result confirms that the variation in the coercive field is mainly due to the change in the spatial distribution of the local demagnetizing field induced by the presence of holes.…”

“…[4][5][6][7][8] Magnetotransport and hysteresis properties have been investigated in detail, considering different materials and analyzing the role of lattice configuration, hole shape, and geometrical parameters, such as the hole size and the interhole distance. [9][10][11][12][13][14][15][16][17][18][19][20][21][22][23] Magnetic domain structures arising in antidot arrays have been experimentally observed by means of magnetic force microscopy (MFM), Lorentz microscopy, X-ray photoemission electron microscopy, and magnetooptic Kerr effect measurements. [22][23][24][25][26][27][28][29] The patterning introduces a spatially dependent shape anisotropy that allows the nucleation and propagation of domain walls, influencing in this way the reversal mechanism, the remanent magnetization, and the coercive field.…”

“…[22][23][24][25][26][27][28][29] The patterning introduces a spatially dependent shape anisotropy that allows the nucleation and propagation of domain walls, influencing in this way the reversal mechanism, the remanent magnetization, and the coercive field. [9][10][11][12][13][14][15][16] A fourfold anisotropy has been found in square-lattice geometries, while hexagonal and honeycomb configurations exhibit a sixfold symmetry. 9 Particular attention has been devoted to the nucleation and propagation of discrete domain chains, to explore the possibility of controlling domain walls with well-defined magnetic configurations.…”

Magnetization reversal in cobalt antidot arrays

“…Antidot arrays are particularly of interest because, as a result of the stray field energy associated with the holes, their introduction into a continuous magnetic thin film or multilayer system will significantly modify the magnetic properties resulting in novel domain configurations, additional magnetic anisotropies, and modification of the magnetization reversal, which in turn affects the switching fields and magnetoresistance behavior. [6][7][8][9][10][11] By choosing a specific antidot geometry, with a given antidot size, antidot separation, and lattice symmetry and orientation, it is therefore possible to control the magnetic properties. The dynamic behavior of antidot arrays is also attracting much interest because the spin wave spectra is dramatically different to that of continuous magnetic thin films, [12][13][14][15] with localized modes occurring in specific regions confined by the holes within the antidot lattice.…”