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An investigation into the structural and magnetic properties of sputtered Fe1-xCrx thin films is presented.

The Tb(Fe0.55Co0.45)1.5 films are fabricated by rf magnetron sputtering from a composite target using a x-ray diffraction, vibrating sample magnetometer. The study shows that Co substitution, coupled with the effects of zero-field annealing, results in an enhancement of both the low-field and the saturation magnetostriction.

Sputtered Fe/Tb ferrimagnetic multilayers were deposited on needle-shaped substrates.

This paper discusses the dependence of Fe thickness on the temperature transition and compensation in Fe/Tb multilayers using Heisenberg bilayer model and Monte Carlo simulations.

Structural and magnetic properties of sputtered Fe/Ti multilayers with Ti thicknesses have been studied using conversion electron Mossbauer spectrometry, x-ray diffraction and TEM, as well as magnetization measurement. Particular attention is paid to the correlation between their magnetic properties and their interfacial structures. Fe layers with thickness of less than 1 nm were alloyed forming an amorphous TiFe(sub2) phase. The iron-rich cyrstalline Fe-Ti alloy was formed as the Fe-layer thickness increases.

Amorphous and crystalline sputtered Tb/Fe multilayers were annealed at various temperatures in a high-vacuum furnace and examined at 300 deg K by x-ray diffraction and conversion electron Mossbauer spectrometry to investigate the effect of annealing on structural and magnetic characteristics. The perpendicular magnetic anisotropy improved at low annealing temperature because of a demixing process which sharpens the interfaces. The mixing of layers gradually destroyed the layered structure at intermediate annealing temperatures. At high temperatures, crystallization of bcc-Fe and hcp-Tb occurred.

The eight-state Potts model on the two-dimensional quasiperiodic octagonal tiling with free boundary conditions, has been investigated by a Monte Carlo simulation, to identify the nature of a temperature-driven transition. Drastic free boundary effects of the numerical data, strongly disturb probability distributions of the internal energy, as well as the scaling behaviour of the specific heat.

Laser-assisted tomographic atom probe is used to study sputtered Tb[Co.sub.2.5] 25 nm/Fe 20 nm multilayers. Results reveal that a stronger Fe-Co mixing is present at the top of the crystalline iron layers as compared to the top of amorphous TbCo layers.

Abstract: Different natures of the magnetization reversal are studied by means of magnetization and magnetostriction measurements for magnetostrictive “spring-magnet” multilayers of TbFeCo/Fe with a fixed Fe layer thickness of 10nm and variable TbFeCo layer thickness of 12, 16 and 20nm. In such multilayered systems, magnetization reversal occurs at different coercive fields for each layer related to formation of the domain wall at interfaces. The results show that at low temperatures, transition from the ferromagnetic saturation state (with domain walls) to the ferrimagnetic transient saturation state (without domain walls) takes place by the reversal of the magnetic moments in the high-magnetization Fe layers. This process is governed by large magnetic anisotropy of the TbFeCo layer. Increasing temperature, this anisotropy decreases and transition results from the reversal of magnetic moments in the small magnetization TbFeCo layers. Formation of the domain wall at interfaces is clearly evidenced by the negative contribution to the parallel magnetostriction. [Copyright &y& Elsevier]