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Laser-induced irreversible modifications of magnetic properties of molecular beam epitaxy grown X/Co/Y trilayers on Al2O3 substrates were investigated, with combinations of nonmagnetic metals Pt and Au as buffer X and capping layer Y. It is shown that the formation of regions with irreversibly rotated magnetization from in-plane to out-of-plane orientation occurred for Pt/Co/Pt, Pt/Co/Au, and Au/Co/Pt trilayers. In the Au/Co/Au system, the modification of magnetic properties was negligible. Pt/Co/Pt trilayers were also deposited by sputtering on Si/SiO2 substrates. In this case, a significant suppression of laser-induced magnetic modifications was observed and correlated with the lower thermal conductivity of the Si/SiO2 substrate. [ABSTRACT FROM AUTHOR]

Spatial distribution of magnetization in an ultrathin ferromagnetic Co layer with a lateral gradient of magnetic anisotropy, while approaching spin reorientation transition (SRT) (from perpendicular to in-plane magnetization alignment), has been investigated by means of micromagnetic simulations in the 2-D mode, using OOMMF software. The geometry of the out-of-plane-magnetized domains (parallel stripes, labyrinth, and bubbles) has been found to be dependent on both the initial distribution of magnetization and the direction of the applied magnetic field. A fast decrease in the domain size has been observed while moving toward SRT. In the experiment, Pt/Co/Pt layers with initial in-plane magnetization orientation have been irreversibly modified by femtosecond laser pulses. In the irradiated spot, rings with induced perpendicular magnetic anisotropy have been formed, resulting in an appearance of several local SRTs. Magnetic domain structure in the SRT regions has been visualized using magnetic force microscopy. The experimental observations are qualitatively explained by the results of the micromagnetic simulations. [ABSTRACT FROM AUTHOR]

We report investigations on temperature-induced transformation of magnetic domain structures in the Fe-rich amorphous glass-covered microwires. The images of domain structures and magnetization reversal process were registered by means of magnetooptical Kerr microscopy. The coexistence of two different types of surface domain structures with helical magnetization components has been found. The obtained results discussed in the frame of the model supposed the stress influence on the domain structure. [ABSTRACT FROM AUTHOR]

Magnetization processes were investigated by employing magnetometry and magnetic domain imaging using magnetooptical longitudinal and polar effects in Fe60Al40 films of 40 nm thickness. The films were initially chemically ordered and weakly ferromagnetic, and a large increase in the saturation magnetization was achieved through chemical disorder induced by Ne+-ion irradiation. Various sample geometries were investigated: 1) continuous film; 2) homogenously irradiated wire; and 3) magnetic stripe-patterned wire. Magnetization reversal and magnetic domains formed under the influence of the above sample geometries are reported. [ABSTRACT FROM AUTHOR]

We report about magneto-optical studies of magnetization reversal processes and magnetic domain structures in rare-earth Bi-substituted iron garnets in a wide temperature range. Measurements were done by a standard magneto-optical technique in Faraday geometry. Changes of both hysteresis loops shape and magnetic domain structures with temperatures indicate the presence of the branching domain structures above 130 K and the compensation temperature at 96 K. [ABSTRACT FROM AUTHOR]

In this paper, magnetic states and magnetization reversal of perpendicularly magnetized monodomain dots with a lateral size of hundred nanometers induced in a Co layer by a structured buffer are investigated by means of magnetic force microscopy. The experimental results have been successfully reproduced by micromagnetic simulations using an object-oriented micromagnetic framework. The factors responsible for the dots' behavior are discussed in details. [ABSTRACT FROM AUTHOR]

Results of domain structures observation of individual Ni80 Fe20 and Co sublayers in sputter deposited (NIFe/Au/Co/Au)io multilayers, using an element-sensitive method: the photoemission electron microscopy combined with soft X-ray magnetic circular dichroism, are presented. Also, overall domain structures were studied with magnetic force microscopy. The studies allowed us to reveal submicron stripe domains in the investigated samples and the replication of the stripe domains from the Co layers with perpendicular anisotropy to the NiFe layers with easy-plane anisotropy. [ABSTRACT FROM AUTHOR]

Material selective sensitivity of a magneto-optical polar Kerr effect to magnetizations of films from different materials in a multilayer system is presented. The method is supported by rigorous modeling of magneto-optic response from the multilayer system and by experimental demonstration on the periodic cobalt-permalloy multilayers [Ni[sub80] Fe[sub20] (2 nm)/Au(2 nm)ICo(0.4, 0.8, and 1.2 nm)/Au(2 nm)]10. [ABSTRACT FROM AUTHOR]

The aim of the paper is to study the magnetization processes and magnetic domain structure in epitaxial ultrathin Co films grown on stepped Si(111) substrates. The surfaces after Cu and Au/Cu coverage were investigated using in situ STM technique. The thickness driven evolution of hysteresis loops corresponds to spin-reorientation transition above 7 monolayers (ML) Co thickness. The in-plane magnetic anisotropy symmetry was deduced from magneto-optical (MOKE) hysteresis loops. The experimental data are discussed taking into account contributions of both perpendicular and in-plane uniaxial step-induced anisotropy. The preference of domain wall propagation for 3 and 5 ML Co thicknesses could be explained by the step-induced in-plane magnetic anisotropy determined from in-plane MOKE measurement. [ABSTRACT FROM AUTHOR]

The influence of the Co layer thickness as well as the number of repetitions N on the magnetic properties of (Co/Au)N multilayers was investigated systematically using magneto-optical techniques, vibrating sample magnetometry, and magnetic force microscopy. The studies focused on the characteristics of magnetic hysteresis loops in connection with magnetic domain structure parameters. Increasing the repetitions number, an out-of-plane magnetization ordering is created for Co layers with a thickness larger than the single-layer thickness at which the spin reorientation transition occurs. [ABSTRACT FROM AUTHOR]

We report investigations on crossed magnetic field-induced transformation of surface domain structure in amorphous glass covered microwires. The study has been performed by a magneto-optical Kerr effect technique using optical microscopy. The existence of elliptic domain structure has been demonstrated experimentally. The formation of the domain structure with periodically inclined domain walls caused by the circular magnetic field was found in the surface of microwires. [ABSTRACT FROM AUTHOR]

We report investigations on influence of high-frequency electric current on surface magnetization reversal and surface domains nucleation in amorphous glass covered microwires. Magneto-optical Kerr magnetometry and microscopy have been used. A strong change of surface magnetization reversal and the transformation of the surface domain structure induced by electric current within a frequency range of 100 Hz–15 MHz have been found. [ABSTRACT FROM AUTHOR]

In this paper, we report investigations on circular magnetic domain structure in amorphous microwires. Polar magneto-optical Kerr microscopy was used for the observation of the magnetic domains images. The surface magnetization reversal is determined basically by the circular domains nucleation. For the first time, the rearrangement of the surface domain structure is observed as a part of the magnetization reversal process in amorphous microwires. [ABSTRACT FROM AUTHOR]