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Electric manipulation of magnetization is essential for the integration of magnetic functionalities in integrated circuits. Spin-orbit torque (SOT), originating from the coupling of electron spin and orbital motion through spin-orbital interaction, can effectively manipulate magnetization. Symmetry breaking plays an important role in spintronics based on SOT. SOT requires inversion asymmetry in order to have a net effect on magnetic materials, which is commonly realized by spatial asymmetry: a thin magnetic layer sandwiched between two dissimilar layers. This kind of structure restricts the SOT by mirror and rotational symmetries to have a particular form: an “antidamping-like” component oriented in the film plane even upon reversal of the magnetization direction. Consequently, magnetization perpendicular to the film plane cannot be deterministically switched with pure electric current. To achieve all-electric switching of perpendicular magnetization, it is necessary to break the mirror and rotational symmetries of the sandwiched structure.

Using the double high-speed photography method, the dynamics of domain walls in a ferrite–garnet film is studied under an in-plane magnetic field close in magnitude to the anisotropy field. To explain the obtained nonlinear relation between the domain wall mobility and dc magnetic field oriented in the film plane perpendicular to the domain wall plane, we use the assumption about the dependence of the damping parameter on the in-plane field, which becomes appreciable under the in-plane field exceeding 40% of the sample anisotropy field.

We study the influence of an antimony sublayer (10 nm) on the structure and galvanomagnetic properties of bismuth–antimony films with an antimony content of 3 and 5 at %, up to 1-µm thick, obtained by discrete vacuum evaporation, as well as films recrystallized by the zone-melting method. When using an antimony sublayer, blocks with a significant deviation of the trigonal axis from the normal to the film surface are revealed. The area of such blocks increases with increasing antimony concentration. In recrystallized films, when using a sublayer, the orientation of the trigonal axis is maintained perpendicular to the film plane and adhesion to the substrate is improved. Single-crystal films with an antimony sublayer are of interest for studying the possibilities of deformation engineering for modifying the band structure of thin, highly perfect films of bismuth–antimony solid solution in order to get the desired properties.

When dielectric elastomer materials are used for power generation, bias voltage is applied at both ends of dielectric elastomer film, and there are equal amounts of heterogeneous charges on both sides of the film, so Maxwell electrostatic force is always coupled in the process of power generation. In order to investigate the distribution of Maxwell stress in dielectric elastomer material under electric field, the electrostatic model of dielectric elastomer generator is established in COMSOL finite element simulation software environment in this paper. The distribution of electrostatic force is studied from two aspects of theoretical derivation and simulation, and the magnitude and direction of electrostatic force are determined. The simulation results show that the Maxwell electrostatic force can be equivalent to the tensile force along the film plane and the extrusion force perpendicular to the plane, and they are the same.

The domain structures in the Co(0001) film with a thickness of 200 nm containing Bloch lines are studied in this work using the 3D micromagnetic modeling method. It is shown that Bloch lines include Bloch points in the cases when the domain walls are vortex-like. The transformation processes of domain structures containing Bloch lines are considered in the course of the film magnetization to saturation and subsequent decrease in the magnetic field to the zero value (for the fields lying either in the film plane or along the normal to the film). The configurations of magnetization in Bloch lines are analyzed. It is demonstrated that Bloch lines with both vertical and horizontal segments arise upon the application of magnetic field forming some angle with the film plane.

The ferromagnetic resonance (FMR) spectra of epitaxial yttrium iron garnet films are experimentally studied. The field dependences of the FR frequency are used to determine the effective fields induced by the first and second anisotropy constants and the effective uniaxial anisotropy field. The FMR frequency and linewidth are found to increase in the fields lower than 8 Oe applied in the bismuth-containing film plane. This increase is related to the formation of a nonuniform magnetization distribution, which is supported by a direct magnetooptical observation. The FMR spectra are found to be modulated by a set of narrow lines, the amplitude of which is proportional to the FMR signal intensity. The frequency position of the lines is independent of the magnitude and direction of a dc magnetic field. This modulation is shown to be associated with the resonance excitation of transverse elastic vibration modes. The effective magnetoelastic coupling parameter and the linewidth of the elastic vibrations excited by resonance pumping are estimated.

Perpendicular 90 kOe torquemetry analysis of magnetic anisotropy ( $K_{\mathrm {u\bot }}^{\mathrm {exp}}$ ) for L10-typed FePt granular media with various grain boundary materials (GBMs) was conducted. According to the analysis for granular films with a constant GBM volume of 30 vol% deposited at a high substrate temperature, $K_{\mathrm {u\bot }}^{\mathrm {exp}}$ was not dependent on the saturated torque coefficient of fourfold components ( $L_{4\theta }^{\mathrm {sat}}$ ) but was dependent on that of twofold components ( $L_{2\theta }^{\mathrm {sat}}$ ) originating from magnetic grains with $c$ -axes normal to the film plane. Furthermore, $L_{4\theta }^{\mathrm {sat}}$ mainly originated from FePt grains with $c$ -axes parallel to the film plane. $K_{\mathrm {u\bot }}^{\mathrm {exp}}$ also had a strong correlation with grain diameter ( $GD$ ) and degree of order ( $S_{\mathrm {in}}$ ). On the other hand, $K_{\mathrm {u\bot }}^{\mathrm {exp}}$ had no significant correlation with the melting point ( $T_{m}$ ) of the GBM, which indicates that the dominant factor affecting $K_{\mathrm {u\bot }}^{\mathrm {exp}}$ was not phase separation. Based on these evaluations, an increase of $GD$ caused an increase of $S_{\mathrm {in}}$ , regardless of the GBMs, which resulted in enhancement of $K_{\mathrm {u\bot }}^{\mathrm {exp}}$ for the FePt granular films.

Wurtzite AlN films with high Fe concentrations were deposited on Si(100) substrates using radio-frequency sputtering, and the growth process was investigated. X-Ray diffraction (XRD) analysis with parallel incident X-rays showed that a thick film (∼2.5 μm) had a non-polar a-axis orientation, similar to the films deposited on SiO2 glass substrates. Through powder XRD analysis, it was found that non-wurtzite fine crystals and/or amorphous materials formed during the initial stage of deposition, followed by wurtzite nucleation with various orientations of the axes, such as a, m, and r orientations. The XRD results also implied that the a-axis-oriented regions drastically increased with increasing film thickness. Scanning transmission electron microscopy (STEM) and energy-dispersive X-ray spectroscopy analyses suggested that one of the candidates for the non-wurtzite fine crystalline material was γ-Al2O3. STEM analysis also demonstrated that a-axis-oriented single-crystal grains grew from randomly oriented small wurtzite grains that increased in diameter with increasing deposition time. Al K-edge X-ray absorption near-edge structure results suggested that the electronic structure in the polar c-axis direction of wurtzite lying in the film plane developed with deposition time, thereby further supporting the findings of the XRD and STEM analyses.

Influence of different initial states on time behavior of magnetoresistance is studied for nanostructures with magnetization out of films plane. It is shown that two-time dependence of the magnetoresistance reaches plateau in long-time regime with values, which depend on initial state, thickness of ferromagnetic films and temperature.

We report the influence of magnetic NiFe artificial spin ice (ASI) on the transport properties of superconducting Nb thin film. Resistivity (ρ) as a function of temperature (T ~ 1.8 to 300 K) and magnetic field (B ~ 0 to 40 kOe in parallel and perpendicular orientations with respect to the film plane) has been examined for two samples, a plain Nb thin film and a hybrid thin film of NiFe-ASI and Nb (Nb-NiFe). The impact of the magnetic NiFe-ASI on superconducting Nb is clearly visible in the transport properties, where, in comparison with plain Nb, for the Nb-NiFe hybrid thin film: (1) the normal state resistivity increases by a factor ~ 1.5; (2) the superconducting transition temperature (Tc) at B = 0 reduces from 7.31 to 6.51 K; (3) the surface sheath superconductivity vanishes as reflected by the parallel upper critical field, Bc2(T); and (4) the perpendicular Bc2(T) is suppressed in the entire T range. Interestingly, with the applied field, $$ {T}_{\mathrm{c}}^{\mathrm{Nb}}-{T}_{\mathrm{c}}^{\mathrm{Nb}-\mathrm{NiFe}} $$ |B increases in perpendicular and decreases in parallel field orientation. The magnetoresistance measurements near Tc for our Nb-NiFe hybrid thin film show shallow minima revealing matching pinning effects with respect to the ASI square lattice. The results are understood in terms of the thin film nature of our samples, geometrically frustrated magnetism of ASI and the proximity between the magnetic NiFe-ASI and superconducting Nb at the interface.

Results are presented from investigating active and drainage layers of composite films (membranes) UPM-50 and UPM-100 before and after exposure to transmembrane pressure by means of IR spectra of reflection, X-ray scattering, and raster electron microscopy. It is found that changes in the IR spectrum of the working sample are caused by the destruction of weak bonds of C=O···H–N amide fragments of the polysulfonamide film. A drop in (C=O) vibration frequency ν by Δν = 20 cm−1 indicates redistribution of the electron density between C=O-groups and benzene rings as a result of the inductive effect of coupling, which results in the formation of charged functional groups CO−. The presence of CO– groups fragments a new supramolecular structure whose stability due to the dipole–dipole interaction of carbonyl anions. X-ray scattering of the initial and working samples in the 10°–35° range of angles 2θ is determined by three intense reflections at angles 2θ ~ 17.23°, 22.24°, 25.41° from crystallographic planes ((010), (100), and (110)) corresponding to the crystalline structure of lavsan (polyethylene terephthalate). A comparative analysis of the reduced intensities of reflections from crystallographic planes (010), (100) and the sizes of lamellas indicates that transmembrane pressure initiates conformational rearrangement of crystallites with crystallographic axis b oriented parallel to the film plane.

A low-temperature feature is detected in nanogranular magnetic films with perpendicular anisotropy that have a low-field positive magnetoresistance: positive magnetoresistance is observed during the initial magnetization of the demagnetized sample, but is absent when the magnetic field is removed and/or during subsequent magnetizations. This effect is studied using a Cox(Al2On)1−x film with x = 0.60, consisting of Co metal nanogranules in an Al2On insulating matrix with n close to 3. It is found that together with perpendicular anisotropy, the film has local in-plane anisotropy with randomly oriented easy axes, which prevents the reorientation of the granules’ magnetic moment projections in the film plane below a certain blocking temperature. The restoration of the local short-range order in the orientation of the magnetic moments of the demagnetized film’s neighboring granules, which is optimal for conductivity and is destroyed by the introduction of a magnetic field, is prevented at temperatures below the blocking temperature and is not restored during subsequent cycles of introducing/removing the magnetic field without heating to temperatures above the blocking temperature.

For plastic spintronics, it has thus far been a challenge to develop a (magnetic nanostructures)/polymer heterostructure at low temperature due to the thermal sensitivity of polymers. In this context, half-metallic magnetite (Fe3O4) films of different thicknesses were coated on flexible polymethyl methacrylate (PMMA) substrates by reactive sputtering at 300 K. Grain size and thickness increased from ~10 nm to ~34 nm and 50 nm to 400 nm with an increase in the deposition time from 165 to 1335 s, respectively. Moreover, a sharp rise in grain size was observed when the thickness of the film reached 200 nm, and finally, saturation took place at 400 nm. X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED), and X-ray photoelectron spectroscopy (XPS) studies confirmed the absence of the γ-Fe2O3 phase and thus the successful deposition of Fe3O4 thin films on the PMMA substrate. Parameters as such as Verwey transition (Tv) (~125 K), saturation magnetization (Ms) (~354 emu/cm3) and magnetoresistance (MR) (−8.6% under 60 KOe at 300 K) under H ∥ Film plane were obtained for Fe3O4/PMMA heterostructures with a film thickness of 200 nm. The resistivity (ρ), Tv, Ms and MR were hardly affected on several bending tests, proving that Fe3O4/PMMA heterostructures are exciting materials for future flexible spintronics.

Spin valves comprising a synthetic antiferromagnet and a CoFe/Dy/CoFe structure in the pinned layer were prepared by magnetron sputtering. It is shown that the Dy layer is characterized by crystallites, the [0002] direction of which is perpendicular to the film plane; a part of nanostructure, in which the spin-dependent electron scattering occurs, is characterized by smooth interfaces. Variations of magnetotransport properties of the spin valve, which are due to the formation of antiferromagnetic order in the dysprosium layer, are observed. Peculiarities of noncollinear magnetic order of the Dy layer were found to depend on the direction of magnetic moments of adjacent layers and magnetic field strength when passing through the Neel temperature.

Magnetic field induced effects in the second-harmonic generation in a thin asymmetric Ta/Co/Pt trilayer film with in-plane magnetic anisotropy are investigated. It is shown that the rotation of the polarization plane of the second-harmonic wave in the longitudinal magneto-optical Kerr effect configuration is as large as 37°, which corresponds to a relative contribution from the magnetic field induced component of the second-harmonic field of about 30% and significantly exceeds the magnitude of the same effect for Co/Pt bilayer structures. It is shown that magnetization reversal in the Ta/Co/Pt structure occurs via the rotation of the magnetization vector within the film plane, and its direction is determined by the orientation of the easy magnetization axis of the structure relative to the applied field. The odd in magnetization contribution is experimentally observed in the intensity of the second harmonic in the longitudinal Kerr effect geometry, although it is forbidden by symmetry for the surfaces of uniformly magnetized structures.

The structure and magnetic properties of CoPt–Al2O3 nanocomposite films synthesized by the annealing of Al/(Co3O4 + Pt) bilayers on a MgO(001) substrate at 650°C in vacuum are investigated. The synthesized composite films contain ferromagnetic CoPt grains with an average size of 25–45 nm enclosed in a nonconducting Al2O3 matrix. The saturation magnetization (Ms ~ 330 G) and coercivity (Hc ≈ 6 kOe) of the films are measured in the film plane and perpendicular to it. The obtained films are characterized by a spatial rotational magnetic anisotropy, which makes it possible to arbitrarily set the easy magnetization axis in the film plane or perpendicular to it using a magnetic field stronger than the coercivity (H > Hc).

The effect of Fe and Mn impurities on the magnetic parameters of ZnO wide-gap semiconductor films produced by high-frequency sputtering with wide variations in the defect concentration is studied. The introduction of Mn and Fe magnetic impurities brings about the existence of a magnetically ordered state in the semiconductor matrix, with different positions of the axis of easy magnetization. In the case of doping with Mn, this axis lies perpendicularly to the film plane, and in the case of doping with Fe, this axis lies in the film plane.

A floating-catalyst spray pyrolysis method was used to synthesize carbon nanotube (CNT) thin films. With the use of ammonium chloride as a pore-former and epoxy resin (EP) as an adhesive, CNT/EP composite films with a porous structure were prepared through the post-heat treatment. These films have excellent thermal insulation (0.029–0.048 W·m−1·K−1) at the thickness direction as well as a good thermal conductivity (40–60 Wm−1·K−1) in the film plane. This study provides a new film material for thermal control systems that demand a good thermal conductivity in the plane but outstanding thermal insulation at the thickness direction.

This paper identifies and characterizes complex core-shell morphologies in thin films of a polybutadiene-block-poly(2-vinyl pyridine)-block-poly(tert-butyl methacrylate) (BVT) triblock terpolymer. The spin-coated BVT film develops into two distinct microphase separated structures with thickness variation during solvent annealing in a well-controlled atmosphere of THF vapor. Cylinders parallel to the film plane are found in thinner terraces and featureless areas that are characteristic of the lying lamella phase, or disordered structures are found in thicker terraces. Underneath the surface, we found that these microphase separated structures exhibit core-shell morphologies, i.e. surface ablation revealed core-shell cylinders and core-shell perforated lamellae under a cover layer in each terrace. Time-resolved study upon solvent annealing shows that the dynamics of microdomain evolution are affected by the extent of annealing time. The structural development in the BVT terpolymer films on corrugated supports demonstrates flow-field-induced sequenced ordering of the microdomains.

The ultrafast dynamics of photoexcited carriers and coherent phonons in ultrathin Bi2Te3 thermoelectric films are studied through transient differential transmission spectroscopy. An ultralow frequency coherent optical phonon at 0.16 THz emerges, especially in ultrathin films, and it is ascribed to interlayer breathing modes. It can divide the ultrathin films into two groups which have out-of-phase vibration along the normal of a film plane, causing a destructive interference between in-plane propagating thermal waves in the two groups of quintuple layers, and thus possibly reducing the thermal conductivity of the ultrathin films. The excitation power dependence of ultrafast dynamics reveals carrier-carrier scattering dominating thermalization, which provides a microscopic understanding of the reported high electrical conductivity and anomalously high power factor of ultrathin Bi2Te3 films at room temperature.

We demonstrated atomic diffusion bonding (ADB) of wafers using AlN films at room temperature. Results showed that crystal lattice rearrangement occurred at the bonded interface and integrated AlN film with c-axis perpendicular to the film plane formed.

In this work, we study the magnetoelastic behavior of ${\mathrm{Fe}}_{1\ensuremath{-}x}{\mathrm{Ga}}_{x}$ ($0.11lxl0.19$) thin films, grown on glass and oxidized Si(100) amorphous substrates, that present an isotropic crystalline texture in the film plane. The magnetoelastic coupling coefficients are obtained through the cantilever deflection technique. We find that the magnetoelastic response is larger for samples grown on glass with respect to those grown on Si(100), and such a response increases for larger Ga concentrations for both substrates used. Furthermore, the increasing substrate temperature during growth does not appear to have a significant effect on magnetoelastic behavior of samples grown on Si(100). From a model that takes into account the elastic grain interaction for isotropic systems, we are able to describe the experimentally observed behavior. We find that the magnetoelastic response of the samples grown on glass are well described by the Voigt model, while the samples on Si(100) present an intermediate response between the Voigt and Reuss models.