This paper presents the results of investigating the impact of temperature on the magnetic properties of Co/Gd/Co and Co/Cu/Co thin-film three-layer systems obtained via ion-plasma magnetron sputtering. The following features of the studied samples were found. In particular, when the temperature changes from 100 to 300[Formula: see text]K, the coercive force of studied systems decreases. The magnetic moment of Co/Cu/Co sample does not dependent on temperature. Strong influence of temperature on the magnetic properties of the studied samples is observed. In particular, a compensation point was found at temperature [Formula: see text][Formula: see text]K for a Co/Gd/Co sample with thickness of gadolinium of 9.0[Formula: see text]nm.

The temperature dependences of magnetic properties and magnetic field behavior of Co/Gd/Co thin-film three-layer systems obtained via ion-plasma magnetron sputtering are studied. The thickness of cobalt layers is 5.0 nm and of Gd layers (t(Gd)) varies from 3.0 to 10.0 nm. The bulk magnetic characteristics of the samples were measured on a vibration magnetometer with an external magnetic field oriented parallel to the plane of the samples. The influence of the temperature and the thickness of a Gd layer on the shape of the hysteresis loops, the values of the magnetic moment m and the coercive force H-C are discovered. In particular, when the temperature changes from 100 to 300 K, the coercive force decreases, and the magnetic moment increases at a temperature above 150 K. The m value decreases with an increase in thickness of gadolinium.

The results of studies of the temperature dependences of the magnetic properties and magnetic field behavior of thin-film three-layer Co/Gd/Co system, obtained by ion-plasma magnetron sputtering, are present. The thickness of the cobalt layers is 5.0 nm, and the thickness of the Gd layers, tGd, varies from 3.0 to 10.0 nm. The bulk magnetic characteristics of the samples are measured on a vibrating magnetometer at the external magnetic field oriented parallel to the plane of the samples. The influence of the temperature and Gd thickness on the shape of the hysteresis loops, the values of the magnetic moment m and coercive force are discovered. In particular, with the temperature changes from 100 to 300 K, the decrease of the coercive force is observed. At a temperature above 150 K, magnetic moment increases. With increasing thickness of gadolinium, the value of m decreases.

Thin Fe 19 Ni 81 films were deposited by magnetron sputtering technique onto cyclo olefin copolymer (COC) flexible polymer substrates. COC/FeNi(15 nm), COC/FeNi(23 nm), COC/FeNi(25 nm), and COC/FeNi(84 nm) composites were obtained and studied using structural, magnetic, and microwave measurements. COC/FeNi(84 nm) composite, which still had certain transparency insured complete protection with respect to the component of microwave signal polarized along the Gunn diode axis (frequency of 10.52 GHz). Even most thin (15 nm) FeNi film was almost as effective as 84 nm film but having much higher transparency acceptable for microfluidic devices. Obtained results indicate that fabricated flexible composites can be used as effective shielding materials in complex multipurpose devices.

A series of permalloy nanofilms on glass substrates was fabricated by use of magnetron sputtering. As-deposited and thermally annealed in air oxidized nanofilms were characterized by the AFM and VSM techniques. For a temperature range of 300-475 degrees C, the magneto-optical figure of merit (FOM) altered in magnitude due to rise in transparency and strong change in the Faraday rotation of the oxidized nanofilms. In the near infrared range, FOM of the 425 degrees C-oxidized nanofilms was more than one order of magnitude larger than that of the as-deposited ones. The observed magneto-optical properties were addressed to material and structural transformations of the as-deposited nanofilms.

Magnetic properties of an interface between cobalt and platinum or tantalum nanolayers have been studied by the optical second-harmonic generation and nonlinear magneto-optical Kerr effect methods. It has been shown that a high sensitivity of the second-harmonic generation method makes it possible to determine the orientation of the easy magnetization axis in the plane of a polycrystalline structure without measurement of the magnetic field dependence of second-harmonic generation. The comparison of the field dependences of magnetic-field-induced second-harmonic generation with the linear magneto-optical effect indicates the difference in the processes of magnetization reversal in Co/Pt and Co/Ta interfaces and the bulk of the cobalt film. In particular, a new linear in magnetization effect has been observed in the second harmonic that is symmetry-forbidden for uniformly magnetized structures.

In recent years, much attention has been paid to the study of magnetoelectric (ME) effects in solids, which was caused by their potential practical applications. Of particular interest are composite multiferroic materials containing ferroelectric and ferromagnetic phases, since significant ME responses may occur in them. This paper is devoted to the study of the inverse ME effect in a two-layered composite sample consisting of a piezoelectric Pb(Zr, Ti)O 3 ( PZT ) plate and an amorphous FeCuNbSiB ferromagnetic ribbon. It was found that the inverse ME effect depends on the magnitudes of the external magnetic field H , the electric voltage U and on the mutual orientation of H and U .

Structural and magnetic characteristics and behavior of thin-film Co/Gd/Co systems obtained by ion plasma sputtering in a magnetic field are reported. X-ray studies showed that cobalt layers in all investigated samples have a nanocrystalline structure. The mean roughness Ra of the surface of the samples does not exceed 0.5 nm and is independent of the Gd layer thickness. The shape of hysteresis loops observed for the Co/Gd/Co system depends of the thickness of the Gd layer, tGd. The dependence of the saturation field HS on tGd has an oscillatory character. This fact is explained by interaction of the Co layers through the intermediate Gd layer.

This article is dedicated to the influence analysis of the thickness and composition of nonmagnetic intermediate layers, tNM, on the magnetic and structural properties of Co/Mo/Co, Co/Si/Co, Co/Bi/Co and Fe1/PDP/Fe2 thin-film systems, as well as comparing the mechanisms of exchange interaction between ferromagnetic, FM, layers through NM spacers. The thicknesses of Co layers are equal to 5.0 nm and the thickness of Fe layers is varied from 14.0 to 50.0 nm. The thickness of NM layers, depending on its composition, is changed from 0.2 to 50.0 nm. It is found that the hysteresis loops for some samples measured in a magnetic field applied parallel to the easy magnetization axis have a rectangular form and for others – more complex two-step ones. The saturation field, HS, of Co/Mo/Co, Co/Si/Co and Co/Bi/Co samples oscillates in magnitude. These data are explained by the presence of exchange coupling between the Co layers through a NM spacer. Fe1/PDP/Fe2 samples have a two-step hysteresis loops, which at tPDP ≥ 10 nm are explained by the exchange coupling between the Fe layers through the PDP layer, and at tPDP > 10 nm - by the magnetostatic interaction between the Fe layers due to the difference in their thickness.

Magnetization induced effects in optical second harmonic generation from interfaces between heavy and ferromagnetic metals reveal an important role played by magnetic anisotropy and second-order in magnetization effects in their nonlinear response.

AbstractStructural and magnetic characteristics and behavior of thin-film Co/Gd/Co systems obtained by ion plasma sputtering in a magnetic field are reported. X-ray studies showed that cobalt layers in all investigated samples have a nanocrystalline structure. The mean roughness R a of the surface of the samples does not exceed 0.5 nm and is independent of the Gd layer thickness. The shape of hysteresis loops observed for the Co/Gd/Co system depends of the thickness of the Gd layer, t _Gd. The dependence of the saturation field H _S on t _Gd has an oscillatory character. This fact is explained by interaction of the Co layers through the intermediate Gd layer.

Results are presented from investigating the structural and magnetic characteristics of Co 69 Fe 4 Cr 4 Si 12 B 11 amorphous microwires with magnetic core diameters of 35–360 µm, obtained using an updated Ulitovskii–Taylor approach. It is found that the microwires have stable geometric dimensions along their lengths and almost defect-free surfaces. They are characterized by high plasticity and strength, and their magnetic characteristics depend on their diameter. The possibility of the microwires’ practical application is shown.

Magnetic planar nanostructures composed of ferromagnetic and heavy metals are a subject of intensive studies during the last years. Here we apply the technique of optical second harmonic generation (SHG) to the studies of planar nanostructures based on such materials, where the high sensitivity of the SHG probe to the spatial and temporal symmetry breaking is of principal importance. Based on the analysis of the SHG magnetic field dependencies, we show a clear difference of the magnetic behavior of the interfaces and of bulky materials, as well as additional features attributed to specific interfacial chiral magnetization distributions.

Nonlinear magneto-optical Kerr is used to study the magnetic properties of thin bilayer films composed of cobalt and two different non-magnetic metals, platinum and tantal. Our experiments reveal different nonlinear-optical response of these two types of structures related to specific magnetic properties of Co/Ta and Co/Pt interfaces.

Electrically conductive polymers, created at the end of XX century, attract the attention of researchers due to variety of their mechanical and optical properties, as well as high conductivity. Studies conducted to date show the ability of a polymer to transition from low conductivity to a highly conducting state that is close to metallic and has a strong anisotropy. Due to the above properties, they are widely used as functional elements in devices of microelectronics. At the same time, the magnetic characteristics and behaviour features in magnetic field of polymers, in particular, poly diphenylene phthalide (PDP), have not been studied practically. The present work is devoted to the results of investigation of the magnetic properties of Fe/PDP/Fe thin-film systems. (C) 2017 Elsevier B.V. All rights reserved.

Surfaces and interfaces of magnetic nanostructures can reveal rather interesting and unusual properties that differ substantially from those of bulky materials. Here we apply the surface-sensitive method of optical second harmonic generation (SHG) for the studies of magnetization induced effects that appear in the nonlinear reflection from interfaces between ferromagnetic (Co) and heavy metals (Pt, Ta, W, Au, Ag, Cu). We demonstrate the appearance of magnetization induced variation in the p-polarized SHG intensity in the geometry of the longitudinal magneto-optical Kerr effect that is forbidden for homogeneous magnetic structures. This confirms the existence of chiral magnetic states at heavy metal/ferromagnet interfaces that appear due to the surface-induced Dzyaloshinskii-Moriya interaction. The related nonlinear chiroptical effect in the SHG intensity is proportional to the dc flexo-electric polarization that is shown to exist for chiral magnetic states at the considered interfaces.

The structural and magnetic properties of thin-film Fe/poly(diphenylene phthalide) (PDP)/Fe systems are studied, along with the behavior of these systems in magnetic fields. The mean surface roughness of the studied samples is around 5–8 nm, and local near-surface magnetic properties show variation within 10%. The samples are characterized by two-step hysteresis loops, the step size depending on the thickness of the polymer layer and the difference in the thickness between the magnetic layers. The results are explained by the effects the exchange interaction between the magnetic layers, mediated by the PDP interlayer, has on the behavior of our samples in a magnetic field.

The results of investigation of the structural and magnetic characteristics of Co/Cu/Co thin-film systems obtained by magnetron sputtering on glass substrates are presented. The thickness of the cobalt layer in all samples was 5 nm and the thickness of the copper layer was varied from 0.5 to 4 nm. The saturation field H S of the studied samples was found to oscillate in magnitude with changes in the copper-layer thickness with a period on the order of 1 nm. The maximum values of H S are observed for the thin-film systems with tCu = 1.4, 2.2, and 3.2 nm. The hysteresis loops measured for these systems in a magnetic field applied along the easy magnetization axis of the samples have a two-stage shape, while for the samples with other values of tCu the hysteresis loops are rectangular. These data are explained by the presence of exchange coupling between the ferromagnetic layers through a copper spacer and its oscillating behavior with changing tCu.