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Spintronic terahertz (THz) emitters have been shown to be a cost-efficient source for use in time-domain THz spectroscopy. The use of external magnetic fields to control the polarity of the THz emission provides an opportunity to measure the magnetization of spintronic materials as well as shaping THz emission. Here, we demonstrate an efficient method of measuring magnetic hysteresis with material sensitivity and speed several orders of magnitude greater than typical magnetometry methods. In addition, we utilize the rapid control of material magnetization for lock-in detection in time-domain THz spectroscopy of spintronic emitters. The ability to rapidly control and measure the material magnetization on very small volumes provides an opportunity to study magnetic hetero-structures with sub-micron spatial resolution. [ABSTRACT FROM AUTHOR]

(100- x) Sr0.7La0.3Fe11.75Co0.25O19–(x) CoFe2O4 composites were synthesized by the one pot sol–gel auto-combustion method. The individual phase purity, morphology, and magnetic hysteresis loop of the composite magnet were analyzed by x-ray powder diffraction, field emission scanning electron microscopy and vibrating sample magnetometer, respectively. The apparent observation of the room temperature hysteresis loop indicates the existence of interfacial exchange interactions. Nevertheless, saturation magnetization (Ms) follows the trend of Vegard's law. The nature of magnetic interaction and its dependency on the amount of each phase were analyzed by employing the Thamm–Hesse plot. The critical size of the soft phase particle did not corroborate with the results of Δ M v s H plot. However, this synthesis method is found to be successful in obtaining single-step magnetization reversal in hard–soft composite magnets. The deviation from ideal non-interacting Stoner–Wohlfarth particles puts the single hard phase into the limelight. The (BH)max in the range of 1.07–0.98 MGOe has been obtained for the synthesized composite magnet. [ABSTRACT FROM AUTHOR]

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The Stoner–Wohlfarth model is a classical model for magnetic hysteresis of single-domain magnets. For two-dimensional (2D) magnets at finite temperatures, the Stoner–Wohlfarth model must be extended to include intrinsic strong spin fluctuations. We predict several fundamentally different hysteresis properties between 2D and 3D magnets. The magnetization switching diagram known as the astroid figure in the conventional Stoner–Wohlfarth model becomes highly temperature dependent and asymmetric with respect to the transverse and longitudinal magnetic fields. Our results provide new insights into the spintronics applications based on 2D magnetic materials. [ABSTRACT FROM AUTHOR]

The inorganic multiferroic compounds Bi0.9Sm0.1Fe1 − xVxO3 (x = 0.0, 0.015, 0.03, and 0.045) were prepared by the solid-state reaction method. X-ray diffraction analysis confirmed the rhombohedral perovskite-like structure with minor traces of the impurity phases Bi2Fe4O9 and Bi25FeO40. The lattice parameters a and c, and the volume of the hexagonal unit cell were extracted from the X-ray diffraction data and found to increase as the V5+ content is increased. The average crystallite size was estimated to be in the range 380–415 Å. Fourier transform infrared spectroscopy confirmed the rhombohedral perovskite-like structure via the vibration bands of the octahedral FeO6 group observed between 410 and 570 cm−1. A differential scanning calorimeter was used to record the thermal scans which revealed that the compounds have undergone crystalline phase transitions at temperatures in the range 300–320°C. A 4.5% V + 5 substitution has shifted the transition peak by 20°C. The magnetic hysteresis loops taken at room temperature with a vibrating sample magnetometer revealed the ordinary ferromagnetic behavior. The V5+ substitution enhanced the remanent magnetization, but the magnetic coercivity was found to fluctuate around an average value of about 1000 Oe. The compound Bi0.9Sm0.1Fe0.955V0.045O3 exhibited the maximum remanent magnetization. [ABSTRACT FROM AUTHOR]

The magnetic properties and hysteresis loops for the hexagonal Ising nanowire (HIN) with a core-shell structure consisting of mixed spins with the core spin being spin-5/2 and the shell spins being spin-3/2 are studied. The Blume-Capel model is considered by using the mean-field approximation (MFA) based on the Gibbs-Bogoliubov inequality for free energy. The impact of different bilinear interaction parameters (JCC, JSS, JCS) between the core, shell, and core and shell spins, respectively, including the crystal (DC, DS) and external magnetic fields (h = hc = hs) at the core and shell sites, are taken into consideration. In order to obtain phase diagrams on various planes, the thermal changes of the net, core, and shell magnetizations are investigated for various values of our system parameters. It is discovered that the model exhibits only second-order phase transitions when h = 0.0 for D greater or equal to zero, first- and second-order phase transitions for h ≠ 0.0 and compensation temperatures for all h. [ABSTRACT FROM AUTHOR]

The nonlinear ac stationary responses of magnetization and the dynamic magnetic hysteresis of ferromagnetic particles with uniaxial anisotropy acted on by both external dc and ac magnetic fields are evaluated by employing the inertial Landau–Lifshitz–Gilbert equation. Analytical expressions are obtained for the components of the second- and third-order nonlinear susceptibility tensors using the perturbation method. The dynamic nonlinear susceptibility strongly depends on the dc field strength. The effect of inertia on the area and slope of the dynamic magnetic hysteresis loop is demonstrated. In addition to nutation resonance, the main nonlinear effects previously observed in the ferromagnetic resonance region (frequency doubling and appearance of weak subharmonic resonance peaks) are predicted in the nutation resonance frequency region. [ABSTRACT FROM AUTHOR]

The magnetic proximity effect provides a promising way to increase the low Curie temperature (TC) of europium monoxide (EuO) toward or even above room temperature, while keeping its stoichiometry and insulating properties. This work studies EuO/Co bilayers using static and time‐resolved magneto‐optical Kerr effect measurements, and explores the influence of magnetic proximity on TC and on the spin dynamics in EuO. Excitation above the EuO bandgap results in an ultrafast enhancement of the EuO magnetization followed by a demagnetization within nanoseconds. This behaviour is also visible upon selectively photoexciting Co in the EuO/Co bilayer placed in an out‐of‐plane magnetic field, which is attributed to propagation of a superdiffusive spin current from Co into EuO. As the spin dynamics of Co shows a transient thermal demagnetization, the bilayer provides a system where the transient magneto‐optical signal can be tuned in amplitude and sign by varying external parameters such as the sample temperature or pump fluence. Moreover, in a strong excitation regime it is possible to measure the magnetic hysteresis of the underlying EuO, which is present up to room temperature – giving experimental evidence for the presence of a tuneable magnetic proximity coupling between Co and EuO. [ABSTRACT FROM AUTHOR]

The solvothermal reactions of LnCl3·6H2O and MCl2·6H2O (M = Co, Ni) with 2,2′-diphenol (H2L1) and 5,7-dichloro-8-hydroxyquinoline (HL2) gave three 3d–4f heterometallic wheel-like nano-clusters [Ln7M6(L1)6(L2)6(µ3-OH)6(OCH3)6Cl(CH3CN)6]Cl2·xH2O (Ln = Dy, M = Co, x = 3 for 1; Ln = Dy, M = Ni, x = 0 for 2; Ln = Tb, M = Ni, x = 0 for 3) with similar cluster structure. The innermost Ln(III) ion is encapsulated in a planar Ln6 ring which is further embedded in a chair-conformation M6 ring, constructing a Russian doll-like 3d–4f cluster wheel Ln(III)⸦Ln6⸦M6. 2 and 3 show obvious slow magnetic relaxation behavior with negligible opening of the magnetic hysteresis loop. Such a Russian doll-like 3d–4f cluster wheel with the lanthanide disc isolated by transition metallo-ring is rarely reported. [ABSTRACT FROM AUTHOR]

Aluminum-doped copper ferrite nanoparticles synthesized via thermal decomposition were analyzed for Al3+ substitution effects. Nanocrystalline doped copper ferrite with a crystallite size <9 nm was characterized using several advanced techniques, including X-ray diffractometry (XRD), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS). The degree of thermal decomposition used for doping copper ferrite at the nanoparticle level correlates well with the quantitative, dimensional, and structural characterizations. The Scherrer equation and Williamson–Hall method were employed to determine the general lattice strain and constants. Structural properties, such as the oxygen positional parameters, radii of the octahedral and tetrahedral sites, hopping lengths, bond lengths and angles, site bonds, and edge lengths, were determined using XRD patterns. The improved A–B super-exchange interaction was demonstrated by the discrepancy in the theoretically anticipated bond angles. The analysis of magnetic hysteresis (M − H) using a vibrating sample magnetometer (VSM) and XPS confirmed the improvement in the super-exchange interaction. XPS results suggest that Fe and Cu in the crystal lattice are in the form of FeIII and CuII, respectively. The investigation of the degree of inversion, state, and composition using XPS aids to understand the properties of the nanostructured copper ferrites. The saturation and remnant magnetization were determined from hysteresis loops at 1.8 T obtained using the VSM at room temperature. The noncollinear spin and efficient sublattice interactions are responsible for the decrease in M s and M r. [ABSTRACT FROM AUTHOR]

Two dichloride-bridged dinuclear dysprosium(III) complexes based on salen ligands, namely, [Dy(L¹)(μ-Cl)(thf)]2 (1; H2L¹=N,N'-bis(3,5-di-tert-butylsalicylidene)phenylene-diamine) and [Dy2(L²)2(μ-Cl)2(thf)2]2 (2; H2L²=N,N'-bis(3,5-ditert- butylsalicylidene)ethylenediamine) are reported. These two complexes have two short Dy--O(PhO) bonds that exhibit angles of ~90° for 1 and ~143° for 2, leading to clear slow relaxation of the magnetization for 2 and not for 1. Compound 2 has a near-identical core to the recently reported compound [Dy2(L³)2(μ-Cl)2(thf)2] (3; H2L³=N-(2-pyridylmethyl)-N,N-bis(2'-hydroxy-3',5'-di-tertbutylbenzyl) amine). The only substantial difference is the relative angle of the two O(PhO)--Dy--O(PhO) vectors, which is collinear in 2 owing to inversion symmetry and ~68° in 3 due to a molecular C2 axis. It is shown that this subtle structural difference leads to large differences in the dipolar ground states, giving rise to open magnetic hysteresis for 3 and not for 2. [ABSTRACT FROM AUTHOR]

There are several models for magnetic hysteresis. Their key purposes are to model magnetization curves with a history dependence to achieve hysteresis cycles without a frequency dependence. There are different approaches to handling history dependence. The two main categories are Duhem-type models and Preisach-type models. Duhem models handle it via a simple directional dependence on the flux rate, without a proper memory. While the Preisach type model handles it via memory of the point where the direction of the flux rate is changed. The most common Duhem model is the phenomenological Jiles–Atherton model, with examples of other models including the Coleman–Hodgdon model and the Tellinen model. Examples of Preisach type models are the classical Preisach model and the Prandtl–Ishlinskii model, although there are also many other models with adoptions of a similar history dependence. Hysteresis is by definition rate-independent, and thereby not dependent on the speed of the alternating flux density. An additional rate dependence is still important and often included in many dynamic hysteresis models. The Chua model is common for modeling non-linear dynamic magnetization curves; however, it does not define classical hysteresis. Other similar adoptions also exist that combine hysteresis modeling with eddy current modeling, similar to how frequency dependence is included in core loss modeling. Most models are made for scalar values of alternating fields, but there are also several models with vector generalizations that also consider three-dimensional directions. [ABSTRACT FROM AUTHOR]

We have investigated the structural, magnetic, and thermal transport properties of Co 1 − x Ni x Cr 2 O 4 (0 ≤ x ≤ 1) to check the evolution of structural and magnetic properties upon the introduction of the Jahn–Teller active ion Ni 2 + . The x ≤ 0.95 samples can be indexed with a cubic lattice with the space group Fd3m, whereas the x = 0.98 sample undergoes a cubic-tetragonal structural transition, and the x > 0.98 samples belong to a tetragonal lattice with the space group I41-amd at room temperature. All these samples undergo a paramagnetic–ferrimagnetic transition at T C. A spiral ferrimagnetic ordering at T S is suppressed when the amount of Ni is increased, and the abnormal magnetization at T S for the x = 0.6 and 0.8 samples is not pronounced. The measurements of magnetic hysteresis reveal that the x = 0.4 and 0.6 samples possess a rather large coercivity H C compared with the x = 0 and 1 samples. Specifically, the x = 0.4 and 0.6 samples undergo a short-range antiferromagnetic transition above T C. The magnetic properties of the Ni-doped samples can be understood in terms of the magnetic structure model consisting of longitudinal and transverse magnetic sublattices. [ABSTRACT FROM AUTHOR]

The manufacture and study of the properties of magnetic materials requires the development of new automated devices for measuring their magnetic properties. To obtain nanosized materials with a pure phase, it is necessary to modernize former methods and develop new methods for synthesizing materials. As part of this study, a pulse magnetometer was made to study magnetic hysteresis loops. An exceptional feature of this device is the ability to conduct studies of the full cycle of the hysteresis loop using pulsed magnetic fields. M-type BaFe12O19 hexagonal ferrites were synthesized by standard ceramic, mechanochemical, and sol–gel methods. The structural, phase, and magnetic characteristics of the barium hexaferrites were studied. Methods for the synthesis of BaFe12O19 hexagonal ferrites were estimated and compared. Their structural and magnetic properties essentially depend on the method of synthesis. The mechanochemical technology makes it possible to obtain materials without impurity phases through the use of hydrated reagents in the synthesis. The use of sol–gel technology allows the synthesis to be carried out at much lower temperatures. [ABSTRACT FROM AUTHOR]

We present unconventional magnetization in a high-pressure torsion (HPT) CoCrFeNi nanostructured high-entropy alloy: (i) the temperature dependent magnetization protocol and DC susceptibility suggest effects of spin-clustering. Moreover, HPT-processing of the alloy produces a heterogeneous and metastable nanostructure, changing its supermagnetic character: turning superparamagnetic to superspin glass dynamics, (ii) the material shows an inverted magnetic hysteresis loop, an inversion of the central part of the loop where the remanent magnetization points in a direction opposite to the applied field. The exquisite tunability of this inverted magnetism as a function of field and temperature and its reproducibility in a quasi-equilibrium setting make this spin-clustering phenomenon unique. We account for this phenomenon in terms of a non-equilibrium population of oppositely polarized domains of an ordered ferromagnetic state, enabled through the nanostructured, highly distorted, and locally disordered crystalline medium. [ABSTRACT FROM AUTHOR]

Amine-functionalized magnetic microspheres (LS-Fe-NMA) were successfully prepared from lignosulfonate by magnetization and amine modification to remove Cr(VI) from industrial wastewater. In addition to SEM, FTIR, XPS, magnetic hysteresis curves and other characterizations, the adsorption tests were performed in real Cr(VI)-containing industrial wastewater. The experimental influencing factors, such as adsorbent types, LS content in the composites, adsorption time, dosages of adsorbent and adsorption temperature were systematically explored. The results of adsorption models fitting proved that the adsorption conformed to the Langmuir model and the pseudo-second-order kinetic model. At 45 °C, the calculated equilibrium adsorption amount by LS-Fe-NMA in industrial wastewater was 642.11 mg/g. In addition, the adsorption process followed the principle of spontaneous endothermic reaction. It was found that electrostatic interaction, redox and complexation existed during the adsorption process. The excellent adsorption performance and reusability of LS-Fe-NMA for Cr(VI) demonstrates its practical application value in real Cr(VI)-containing industrial wastewater. • Amine-functionalized magnetic microspheres (LS-Fe-NMA) were successfully fabricated. • LS-Fe-NMA was applied for the practical industrial wastewater purification. • LS-Fe-NMA could remove 99.97 % of Cr(VI) from industrial wastewater. • The adsorption process conformed to the Langmuir and pseudo-second-order kinetics model. • Electrostatic interaction, redox and complexation were the main adsorption mechanisms. [ABSTRACT FROM AUTHOR]

The Jiles-Atherton model was widely used in the description of the system with hysteresis, and the solution for the model was important for real-time and high-precision control. The secant method was used for solving anhysteretic magnetization and its initial values were optimized for faster convergence. Then, the Fourth Order Runge-Kutta method was employed to solve magnetization and the required computation cycles were supplied for stable results. Based on the solving method, the effect of the nonzero initial magnetic field on the magnetization was discussed, including the commonly used linear model of the square of magnetization under the medium initial value. From computations, the proposed secant iteration method, with supplied optimal initial values, greatly reduced the iterative steps compared to the fixed-point iteration. Combined with the Fourth Order Runge-Kutta method under more than three cycles of calculations, stable hysteresis results with controllable precisions were acquired. Adjusting the initial magnetic field changed the result of the magnetization, which was helpless to promote the amplitude or improve the symmetry of magnetization. Furthermore, the linear model of the square of magnetization was unacceptable for huge computational errors. The proposed numerical solving method can supply fast and high-precision solutions for the Jiles-Atherton model and provide a basis for the application scope of typical linear assumption. [ABSTRACT FROM AUTHOR]

This review is devoted to an analysis of currently known heterometallic molecular magnets based on an orbitally degenerate 5d metalloligand, [ReIV(CN)7]3−. Heptacyanidometallates with a pentagonal bipyramidal structure of the coordination site and degenerate ground spin state are the source of anisotropic magnetic exchange interactions upon the formation of cyanide-bonded assemblies involving the paramagnetic complexes of the first transition series. Therefore, the development of methods for chemical design using such molecular magnetic modules is extremely important. If for the 4d congener, isoelectronic [MoIII(CN)7]3−, a family of approximately 40 heterometallic compounds, was obtained, whereas for heptacyanorhenate(IV), no more than 20 are known. However, as a result of recent studies, heterobimetallic magnetic assemblies of all dimensionalities have been synthesized, from 0D to 1D, demonstrating slow magnetization relaxation, to 2D networks and 3D frameworks possessing large magnetic hysteresis. The most anisotropic is a 2D network, PPN[{MnIII(acacen)}2ReIV(CN)7]·Solv, with a critical temperature of 20 K and magnetic hysteresis with a record coercivity for cyanide-bridged molecular materials. [ABSTRACT FROM AUTHOR]

This study of nonmagnetic Zn-substitution effect on the charge-ordered behavior of Pr 0.5 Ca 0.5 Mn 1- x Zn x O 3 (x = 0.0, 0.1) compounds reveal the weakening of strong charge-ordered antiferromagnetic state of the parent compound (x = 0.0). Magnetocaloric effect (MCE) has been calculated using a Python package from isothermal M-H data for these samples. A prominent ferromagnetic contribution in the antiferromagnetic matrix for Mn-site doping is observed, which removes the inverse MCE observed in the pristine sample below the charge ordering temperature T CO. Development of ferromagnetism in the doped system exhibits a metal-insulator transition at T MI = 90 K under 7 T magnetic field and large magnetoresistance (> 99 %), which is not observed in parent compound. Magnetic field-dependent hysteresis at low temperature reveals the ferromagnetic metastability and first-order nature of magnetic phase transition. Random occupation of Zn at the Mn-site of the parent compound disrupts 1:1 Mn3+/Mn4+ charge-ordered superstructure of the parent compound which weakens the charge-ordered antiferromagnetic strength promoting ferromagnetism and double-exchange interaction through an enhanced 2 p -3 d hybridization between Mn and O ions. [Display omitted] • Substitution of Zn in Pr0.5Ca0.5Mn1-xZnxO3 compounds affects their charge-ordered behavior. • Strong charge-ordered antiferromagnetic state in the parent compound weakens with Zn substitution. • MCE was calculated using a Python package from isothermal M-H data. • Mn-site doping removes the inverse MCE observed in the parent sample below the charge ordering temperature. • Metal-insulator transition at TMI = 90 K under a 7 T magnetic field and large magnetoresistance (> 99 %) is observed. [ABSTRACT FROM AUTHOR]

This article presents an improved algorithm for identification of the excess loss statistical parameter to get more accurate prediction of multiple harmonic magnetic hysteresis and loss properties of grain-oriented silicon steel sheets. Magnetic hysteresis characteristics of a specimen are measured on a magnetic measurement platform. Static hysteresis property can be simulated accurately by the Preisach model. The excess loss field expression under multiple harmonic magnetizations is constructed based on an extraction algorithm for the statistical parameters of excess loss. According to the equivalence of loss separation and field separation, a new dynamic model is established. In the case of different multiple harmonic magnetizations, the magnetic hysteresis characteristics obtained by predictions are compared with the test results. Also, the influences of peaked flux density, harmonic order, and harmonic content upon the total iron loss are investigated. [ABSTRACT FROM AUTHOR]

For the International Thermonuclear Experimental Reactor magnets, a significant fraction of the Nb3Sn conductors will be operating at a low field (B < 4 T), such as the outer turns of the central solenoid modules and toroidal field winding packs, while so far, the Ic(B,T, Ɛ) parameterization has been derived from measurements carried out at higher fields (B ≥ 7 T). It may not be accurate enough to adopt this parameterization for the extrapolation of the conductors’ operating performance in terms of critical current (Ic) and current sharing (Tcs). The critical current characteristic can be effectively extended to the lower field region by means of a relation between the magnetization and critical current. The parameterization of the derived critical current scaling law Jc(B) is processed for the field range of the magnetization measurement (0 < B ≤ 9 T) and the critical current measurements (7 ≤ B < 12 T) in order to cover the full range up to 12 T. [ABSTRACT FROM AUTHOR]

The statistical theory of magnetic losses provides a simple and general method for the interpretation and prediction of losses in various magnetic materials. However, there are difficulties in assessing the losses since it would require additional experimental data and is seldom available to device designers. In this article, based on the modified dynamic Jiles–Atherton (JA) model by parameters scaling, a parameter extraction process by three successive steps is proposed for identifying 11 effective parameters applicable to different sinusoidal excitation magnetic fields. It provides a promising solution for the prediction of magnetic losses in giant magnetostrictive material (GMM). First, a quasi-static saturation $B$ – $H$ curve is used to obtain five saturation parameters. Four optimization coefficients are then determined using the arbitrary quasi-static minor $B$ – $H$ curve. Finally, on the basis of the nine parameters determined in the former two steps, two dynamic factors are determined using an arbitrary dynamic minor $B$ – $H$ curve. Then, all 11 coefficients were obtained, which could be used to reliably simulate the hysteresis loop of GMM under different sinusoidal excitation magnetic fields and realize the prediction of magnetic loss. The simulation results of the proposed model are in good agreement with the experimental results, which confirm its validity and accuracy. The proposed parameter extraction process can remarkably reduce the required experiment tests, and only three sets of experimental curves are needed to achieve a fast and accurate prediction of GMM magnetic losses. [ABSTRACT FROM AUTHOR]

Angular dependence of coercivity and remanence in 1-D chain of soft permalloy thin truncated conical disks of height 20 nm has been investigated by using finite-element micromagnetic modeling. Base radius ($R$) of the conical disk is varied between 50 and 100 nm. Top radius ($r$) of the conical nanodisk is also varied, such that the ratio $\sigma =r/R $ lies between 0.1 and 1. When the magnetic field is applied along the axis of the 1-D chain, almost square hysteresis loops are exhibited, and corresponding coercive field increases monotonically with $\sigma $. Correspondingly, the remanent magnetization state shifts from $c$ -state to homogeneous magnetization state when $\sigma $ is decreased from 0.9 to 0.5 and then to buckled magnetization state as $\sigma $ is reduced to 0.1. The remanent magnetization and coercive field monotonically decrease with an increase in the angle $\theta $ of applied magnetic field with respect axis of the 1-D chain. This behavior is due to dominating dipolar interaction along the axis of the chain, which makes it the easy axis. The Stoner–Wohlfarth (SW) model is used to approximately estimate the effective uniaxial anisotropy constant arising due to the demagnetization effect of the 1-D chain of conical nanodisks. [ABSTRACT FROM AUTHOR]

This article serves as an overview of existing models of permanent magnets (PMs) for electrical machines. The review study starts with the linear recoil model, which is commonly used to describe the reversible part of the demagnetizing curve. It is a simple model, especially useful for representing materials with high anisotropy, such as ferrite, NdFeB, and SmCo. The model is harder to apply for nonlinear materials, such as Alnico, but still possible since their recoil curves are linear. The study shows how the linear recoil model could be extended to include irreversible demagnetization, temperature dependence, and angular dependence. All such models have their advantages and disadvantages, which will be discussed further. Both the magnetization and the risk of demagnetization are temperature-dependent. It could be noted that NdFeB has an increased risk of demagnetization at high temperatures, while ferrite has it at very low temperatures. The temperature dependence is described and compared for several materials, also including simplifying models. There are different methods to include the inclination angle of an applied magnetic field when studying the demagnetization of PMs. Several models describe different phenomena associated with the underlying dynamics of magnetism. Such models could then consider coercivity mechanisms and coherent rotation of magnetization, both with the Stoner–Wohlfarth model and models of domain wall motions. [ABSTRACT FROM AUTHOR]

In order to investigate the correlation between irradiation-assisted stress corrosion cracking (IASCC) susceptibility and the magnetic properties of austenitic stainless steel after ion irradiation, the magnetic properties and phase transformation were studied using a vibrating sample magnetometer and synchrotron radiation grazing incidence X-ray diffraction (GIXRD) on an irradiated specimen up to 25 displacements per atom. GIXRD indicated that the body-centered-cubic (BCC) phase was introduced in austenitic stainless steel by ion irradiation. Then, magnetic hysteresis loop analysis was conducted to give a quantitative analysis on the BCC magnetic phase under different irradiation damage and annealing temperature conditions. Based on the fact that postirradiation annealing will eliminate IASCC susceptibility at 550°C for 1 h, a correlation between IASCC susceptibility and magnetic properties was discussed, and a corresponding IASCC evaluation method was developed. [ABSTRACT FROM AUTHOR]

The magnetization stability of a YBCO superconductor was numerically studied using the Monte Carlo method. The magnetization-reversal loops of samples with various pinning configurations (periodic and random) were calculated as well as minor loops caused by field inhomogeneities. Hysteresis energy losses were estimated via areas bounded by the minor loops at different temperatures. Samples providing a balance between the critical current, pinning properties, and energy losses, were identified. Among the considered distributions, the homogeneous (periodic) defect configurations showed the highest efficiency. [ABSTRACT FROM AUTHOR]

The Conductor on Rounded Core (${\mathrm CORC}$) cables manufactured by Advanced Conductor Technologies with current densities beyond 300 Amm $^{-2}$ at 4.2 K, and bending diameter of up to 3.5 cm, are considered as one of the strongest candidates for the next generation of high field power applications and magnets. In this paper, we present a full 3D FEM model for their monolayer and bilayer ${\mathrm CORC}$ cables made with up to three and six superconducting tapes respectively, disclosing the full curve of AC losses for the monolayer cable at magnetic fields beyond 60 mT, and the actual distribution of current density along and across the thickness of the superconducting tapes in both designs. The model is based on the so-called H-formulation, allowing to incorporate the true three-dimensionality of the tapes without recurring to 2D thin-film approaches where non-physical surface currents that do not follow the celebrated Bean’s model for type-II superconductors appear. Likewise, good agreement with the experimentally measured AC-losses for the monolayer and bilayer cable have been obtained, with all the details of the model disclosed in this paper. [ABSTRACT FROM AUTHOR]

Magnetically controlled reactors (MCRs) are widely used as reactive power compensation equipment owing to their favorable properties of smoothly adjusting their inductance value through dc bias. However, the dc bias and the rotational magnetization at corner and T-joint areas make the cores of MCRs saturated, resulting in high magnetostriction and vibration. Thus, the electromagnetic vibration analysis of MCRs must consider the vector hysteretic magnetostriction effect. In this article, a vector hysteretic magnetostriction model of silicon steel is proposed by combining the quadratic domain rotation model with the vector inverse Jiles–Atherton model firstly. Then, based on the measured magnetization and magnetostrictive characteristics curves of silicon steel, the model’s parameters are optimized by velocity controllable particle swarm optimization (VCPSO). Finally, the vector hysteretic magnetostriction model is combined with the finite element method (FEM) to simulate the vector vibration characteristics of MCR under dc bias. The simulation results show that the vector property of electromagnetic vibration and magnetic field at the T-joint area is higher than that at other areas. And the MCR vibration test results are consistent with the simulation results, which verify the accuracy of the proposed model in simulating electromagnetic vibration. [ABSTRACT FROM AUTHOR]

An advanced eddy current (EC) sensor incorporating with direct current (dc) magnetizing unit is presented, and its sensor signals are evaluated numerically considering hysteresis behavior. In this article, we propose an efficient method to calculate sensor signals while considering both a moving magnetizer and a high-frequency alternating current (ac) excitation. The calculation process is divided into two sequential analyses. The first step is a time-domain simulation to calculate a gradual change of dc magnetic field from the moving magnetizer. Then, its solution of the magnetic flux density is stored and used to make a subsequent magnetization curve based on the fitting equation-based hysteresis model. The obtained sub-magnetization curve is used for a time-harmonic simulation, and the sensor signal can be finally obtained. We applied the calculation method to a prototype sensor, and it enables to evaluate sensor signals quantitatively at the different magnetizing field and defect size. [ABSTRACT FROM AUTHOR]

We experimentally study a strain-meditated converse magnetoelectric (CME) effect in multiferroic heterostructures consisting of Co2MnSi and Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT). To investigate the CME effect, Co2MnSi films are grown on PMN-PT(001) at various growth temperatures by molecular beam epitaxy. Using magneto-optical Kerr-effect and strain measurements, we find that the remanent magnetization state only for the $L 2_{1}$ -ordered Co2MnSi/PMN-PT is modulated by the application of the lattice strain, while that for the $B2$ -ordered Co2MnSi/PMN-PT is insensitive to the strain. We conclude that the formation of $L 2_{1}$ -ordered structure is needed to obtain an effective CME effect in the Co2MnSi/PMN-PT multiferroic heterostructure. [ABSTRACT FROM AUTHOR]

We report the occurrence of the anomalous Nernst effect (ANE) in polycrystalline perovskite La0.5Ca0.5CoO3. The sample is ferromagnetic (FM) below $T_{C}$ = 147 K and resistivity shows non-metallic behavior above and below $T_{C}$ with only a small negative magnetoresistance (MR) (~2%) around $T_{C}$. The field dependence of magnetization at 10 K shows large hysteresis with a coercive field of 6 kOe but a small magnetization ~ $0.64 ~\mu _{B}$ /Co even in a field of 50 kOe, which indicates the presence of magnetically heterogeneous ground state consisting of FM and non-FM phases. The field dependence of the Nernst thermopower ($S_{xy}$) at low temperatures shows complete saturation, but the magnetization does not. This indicates that the ANE in La0.5Ca0.5CoO3 depends only on the transport properties of the FM phase, while it is not affected by the non-FM phase. Due to the higher value of remnant $S_{xy}$ , the magnetized polycrystalline sample exhibits ANE in the absence of an external magnetic field. [ABSTRACT FROM AUTHOR]

Variable flux memory machines (VFMMs) can have their level of magnet flux density modified by the injection of $d$ -axis current pulses in the armature windings. The use of Fe-Cr-Co magnets as a source of the magnetic field in these machines is still little explored, even if these magnets present interesting thermal and mechanical properties. In this context, this article explores the validation of a standstill magnetization strategy applied in a non-salient single pole pair Fe-Cr-Co-based VFMM designed for high-speed applications in the transportation electrification field. Due to the absence of a well-defined knee on the second quadrant of the hysteresis loop of the magnet used, the methodology commonly seen in the literature for describing the behavior of the recoil lines defining the working points cannot be directly used. Therefore, by the experimental results obtained from the standstill magnetization of the VFMM studied, a new methodology is developed based on the estimation of the remanence in terms of the excitation field characterizing the internal hysteresis loops of the Fe-Cr-Co. The achieved results are compared with the reference obtained from a HysteresisGraph, which represents a closed and ideal magnetic circuit of measurement. The effects of a stator geometry designed with closed slot wedges in the VFMM and the anisotropy shape are explored for justifying the differences observed. [ABSTRACT FROM AUTHOR]

We have systematically investigated the spin-orbit torque (SOT)-induced effective magnetic field in a structure consisting of a Ta heavy metal layer and an antiferromagnetically coupled Mn1.8Ga1/Co2MnSi (CMS) bilayer around the magnetization compensation point by varying CMS film thickness. The efficiency of SOT generation takes the maximum around the compensation point, and it is approximately six times as large compared with that in the devices with a MnGa single structure. The enhancement of SOT efficiency can be explained mainly by the reduction in saturation magnetic moment around the compensation point. Moreover, a significant enhancement of the effective spin Hall angle was observed around the compensation point because of the inversion of the magnetization configuration before and after the compensation point. [ABSTRACT FROM AUTHOR]

The Jiles–Atherton (JA) model is widely used in real-time hysteresis estimation for its better physical understanding and less experimental efforts. However, the inherent defects of JA model may lead to some nonphysical solutions, including negative differential permeability, non-closure of minor loops, and asymmetry of centered minor loops. To deal with such problems, a limiter for differential permeability and a scaling factor for loop closure are generally adopted. However, the existing methods may cause loops’ edges overlapping and cannot solve the asymmetry of centered minor loops. Therefore, a new equation for irreversible magnetization is proposed to solve the negative differential permeability and the edges overlapping. Also, to improve the fitting performance, the JA coefficients are adjusted for different fields and different loops’ turning points. In addition, a scaling factor for centered minor loops is developed to deal with the asymmetry. The factor only needs prior knowledge of minor loops’ starting points. Besides, a modified stack model is proposed, which can extract enough information for coefficients lookup and scaling factors calculation and can realize real-time hysteresis estimation for arbitrary field. Finally, the estimation results are verified by experiments on a toroidal transformer. [ABSTRACT FROM AUTHOR]

• Classic JA model fails to predict the hysteresis accurately, especially the width. • Pinning parameter is better modified as an independent variable on field amplitude. • The improved JA model predicts the hysteresis more accurately than the classic one. Jiles-Atherton (JA) model has been widely used to describe the magnetic hysteresis property of Terfenol-D material. However, the accuracy of the classic JA model is not convincing any more when it is employed to predict the magnetizations under various amplitudes of the applied magnetic fields. This paper measures the magnetic field and magnetization indirectly and approximates the measured results to the best of the classic static JA model. Then it shows that the JA model fails to describe the magnetic hysteresis effectively, especially in computing the hysteresis width. The high computational error is caused from inappropriate value of the pinning parameter to quantify the average energy required to break pinning site. Then the parameter is modified from the constant value to an independent variable on the field amplitude. From the comparisons on the results of the maximum magnetization, maximum magnetization, residual magnetization and coercivity, the performance in describing the hysteresis property of Terfenol-D is obviously promoted by the improved model apparently compared to the classic one. [ABSTRACT FROM AUTHOR]

In the present investigation, sputtering growth of 100 nm thick Co 40 Fe 40 B 20 (CoFeB) film has been investigated in a low temperature range from room temperature (RT) to 400 ℃ on silicon (Si), silicon dioxide (Si/SiO 2), and sapphire (Al 2 O 3) substrates. The film surface morphology, static and dynamic magnetization were measured as a function of growth temperature and substrate. The grown films were further tested as a potential material for microwave device functionality in terms of filter and phase shifter. Surface roughness was lowest for the film grown on Si/SiO 2 substrate at 200 ℃ (0.39 nm) measured from atomic force microscopy. Static magnetic properties measured by tracing magnetic hysteresis loop suggest a soft magnetic behaviour with in-plane magnetic anisotropy. Film saturation magnetization increases with the increase in growth temperature up to 200 ℃ and then decreases from 200 ℃ to 400 ℃. This suggest that the sputtering growth from room temperature to 200 ℃ offer a moderate to low interfacial stress resulting in low defects density. Gilbert damping constant (α eff) of the thin film is obtained from the ferromagnetic resonance measurements in a broad band of microwave frequencies. Damping was lowest (5.4×10−3) in the film grown at 200 ℃ on the Si/SiO 2 substrate which correlates with the roughness and magnetization data. A low value of α eff is desirable for a material to be used in energy efficient spintronics and magnonic applications. The CoFeB films were also utilized in prototype microwave band-stop filter and phase shifter device applications. The filter has been tested in the frequency range from 6 GHz to 25 GHz with an applied magnetic bias up to 4.0 kOe. The frequency tunability with respect to the applied magnetic bias measured to be around 3.64 GHz / kOe. The maximum attenuation of − 4 dB was observed for the film grown on Si/SiO 2 substrate at 200 ℃. Whereas, phase shifter fabricated on Si/SiO 2 /CoFeB film grown at 200 ℃ shows a differential phase shift up to 75° / cm. These results indicates that the CoFeB film deposited at low growth temperature can be a potential material in spintronics and CMOS applications where low temperatures are required for device fabrications. • CoFeB thin films of thickness 100 nm were grown on silicon, silicon dioxide and sapphire substrates by sputtering. • Saturation magnetization and squareness ratio reached their maxima at 200 ℃ grown films on all substrates. • 200 ℃ temperature depicts the perfect stochiometric growth of CoFeB thin film for three substrates. • The lowest values of Gilbert damping (α) were observed for CoFeB thin film grown at a deposition temperature of 200 ℃. • A proto-type band-stop filter and phase shifter using the best CoFeB film developed and tested. [ABSTRACT FROM AUTHOR]

XRD, optical microscope images, and magnetic hysteresis plots of of Ni 0.8 Mg 0.2 Fe 2 O 4 /PVA-CMC nanocomposite films. [Display omitted] • Ni 0.8 Mg 0.2 Fe 2 O 4 spinel ferrite nanoparticles were prepared via sol–gel technique. • Ni 0.8 Mg 0.2 Fe 2 O 4 nanoparticles were used as a dopant material into the PVA-CMC blend to prepare nanocomposites. • The XRD and Raman analysis indicated the interaction between the polymer blend and Ni 0.8 Mg 0.2 Fe 2 O 4 nanoparticles. • Thermal stability of the PVA-CMC/Ni 0.8 Mg 0.2 Fe 2 O 4 films were investigated via DSC analysis. • The bandgap of PVA-CMC blend decreased with increasing Ni 0.8 Mg 0.2 Fe 2 O 4 content. • The magnetic hysteresis plots of composites PVA-CMC/ Ni 0.8 Mg 0.2 Fe 2 O 4 were analyzed at ambient temperature. The production of polymer blend composites with distinctive characteristics is becoming increasingly popular worldwide due to the introduction of innovative properties. Polymer blend films comprising of PVA-CMC matrix doping with Ni 0.8 Mg 0.2 Fe 2 O 4 (2,4,6, and 8 wt%) spinel ferrite nanoparticles were prepared using the solution casting method. The characteristics of the polymer films were analysed using X-ray diffraction (XRD), optical microscope (OM), roughness tester, Raman spectroscopy, and UV–vis spectroscopy. The synthesized of spinel ferrite Ni 0.8 Mg 0.2 Fe 2 O 4 nanoparticles was confirmed by XRD and Raman spectroscopy. The powder's XRD pattern showed the presence of Ni 0.8 Mg 0.2 Fe 2 O 4 in its cubic phase. Similarly, the diffraction pattern of the films confirmed the inclusion of Ni 0.8 Mg 0.2 Fe 2 O 4 spinel ferrite nanoparticles in the PVA-CMC blend. The surface morphology analysis revealed an increase in the film roughness with increasing Ni 0.8 Mg 0.2 Fe 2 O 4 concentration. Differential scanning calorimetry (DSC) explains that the system's thermal stability improves. The absorption edge shifted towards the higher wavelength region with the inclusion of Ni 0.8 Mg 0.2 Fe 2 O 4 in PVA-CMC blend. Consequently, the optical bandgap values were observed to decrease from 5.50 eV to 3.89 eV and from 4.78 eV to 2.89 eV for direct and indirect transitions, respectively, as Ni 0.8 Mg 0.2 Fe 2 O 4 increased from 0 to 8 wt%. The refractive index of the blend films increases from 1.776 for the pure blend to about 3.592, 6.142, 7.789, and 9.680 for 2, 4, 6, and 8 wt% Ni 0.8 Mg 0.2 Fe 2 O 4 respectively. The optical conductivity was found to increase from 1.02 × 1011 to about 9.82 × 1012 S-1 for pure blend and PVA-CMC/8 wt% Ni 0.8 Mg 0.2 Fe 2 O 4 films, respectively. Also, other optical parameters like optical basicity and electronegativity showed an enhancement with the incorporation of Ni 0.8 Mg 0.2 Fe 2 O 4 nanoparticles in the PVA-CMC blend. The magnetic hysteresis plots of composites PVA-CMC/Ni 0.8 Mg 0.2 Fe 2 O 4 exhibited ferromagnetic behavior characterized by a distinct magnetic hysteresis loop. [ABSTRACT FROM AUTHOR]

In this paper, a novel asymmetric-permanent- magnet hybrid-magnetic-circuit variable flux memory machine (AH-VFMM) is proposed. The low coercive force (LCF) permanent magnets (PMs) are located on one biased side of the hybrid magnetic circuit branch, forming an AH configuration. Compared to its conventional symmetric-PM hybrid-magnetic-circuit (SH) counterpart, the proposed design benefits from the reduced usage of high coercive force (HCF) rare-earth magnet, alleviating the magnetic saturation to improve the flux regulation (FR) range, while the excellent load demagnetization withstand (LDW) capability can be still maintained. The topology evolution and operating principle of the proposed machine are introduced and described, respectively. Then, based on the combination of the magnetic equivalent circuit (MEC) method and Schwarz-Christoffel (SC) transformation, a hybrid analytical model is established to quantitatively reveal the mechanism of FR range extension, and facilitate the initial design of the machine. The electromagnetic characteristics of the proposed machine under different magnetization states (MSs) are investigated and compared with those of the conventional SH counterpart. Finally, an AH-VFMM prototype is manufactured, and the experimental measurements are carried out to verify the validity of the proposed design. [ABSTRACT FROM AUTHOR]

The hard particles in metal matrix composite (MMC) coatings can greatly improve the hardness of materials and further affect the mechanical properties. How to accurately evaluate the hardness of MMC coatings using a nondestructive method is always a challenge. The magnetic Barkhausen noise (MBN) has been proven to be very sensitive to the variations of microstructure. Thus, a theoretical model is established in this article to describe the effect of hard particle content on the magnetic Barkhausen activity, based on which the hardness can be evaluated by the MBN method. In this model, the key magnetic parameters of Jiles–Atherton (J-A) theory, the pinning parameter $k$ and reversibility factor $c$ , are dependent on the number and the interparticle distance of hard particles. A stochastic process of Barkhausen activity combined with J-A theory is then described to deduce the variations of hysteresis loop and MBN signals with hard particle contents in MMC coatings. The results show that the peak value of root mean square (rms) of MBN signals decreases, while the full-width at half-maximum (FWHM) increases with the increase in weight percentage of hard particles. Based on the leave-one-out cross-validation (LOO-CV) method, the variation trends of MBN characteristics can be described well by the second-order polynomial fitting. Also, the prediction error between experiment and theory is 15.28% and 17.40% for normalized rms peak value and FWHM, respectively. The variation mechanism of MBN signals is attributed to the anisotropic hypereutectic structure with flower stripe consisting of solid solution and secondary strengthening phase near hard particles, which promotes the pinning sites and hinders the domain wall movement. When the hard particle content is high, especially above 30%, the double peak distortion characteristics of MBN signals are easily induced by the different response of matrix alloy to the applied magnetic field in comparison to the magnetically hard phases in a hypereutectic structure. Finally, the complicated relationship between MBN characteristic values and hardness is deduced by using the hard particle content as an intermediate variable. The results show that our proposed theoretical model and evaluation method in this article can characterize the hardness of MMC coatings well. [ABSTRACT FROM AUTHOR]

Residual stress is one factor involved in the degradation and damage of industrial products. It is important to understand the magnitude and distribution of residual stress to maintain the integrity of a product. Magnetic measurements are a potential nondestructive method for evaluating residual stress in steel because the hysteresis properties are sensitive to stress. In recent years, spatial mapping of local magnetic hysteresis loop has been performed by using the acoustically stimulated electromagnetic (ASEM) method, which obtains the conversion coefficients from local hysteresis parameters to tensile stress. In this study, we demonstrate the evaluation and spatial imaging of tensile residual stress through local hysteresis parameters using welded steel specimens. We confirm that local coercivity can be used for evaluating residual tensile stress in the high-stress region. In addition, the spatial distribution of residual stress is well visualized by imaging the ASEM response signals due to remanent magnetization. [ABSTRACT FROM AUTHOR]

This study details the effect of the co-substitution of Ni4+ ions for Mn4+ ions on the structural, morphological, electrical, and magnetic parameters of BaMn1−xNixO3 (x = 0.1, 0.3, 0.5, 0.7, and 0.9) synthesized by the co-precipitation route. XRD pattern confirmed the hexagonal (P63/mmc (194), z = 2) phase for all samples and an additional significant secondaries phases, such as BaMn2O3, Mn2NiO3, Mn3O4, Mn2NiO4, and NiO for all doping levels. The crystallite size is obtained to be 36.8 to 90.2 nm and independent of Ni content; such a trend in SEM images presented the regular hexagonal platelets of sizes ~ 84–390 nm. Also, the ratio of Gs/Cs varies between 2 and 5. EDX revealed the presence of constituent elements with their weight percentages in BaMn1−xNixO3 products. ρXRD and ρexp are estimated to be around 5.9370 g/cm3. The porosity, P, decreases by 60% with increasing Ni-90%. The σDC increases with increasing temperature impress semiconductor behavior. SPH model is the best fit for the conductivity data. The activation energy is calculated to be (0.21–0.33) eV and increased 3 times with increasing Ni content. The magnetic hysteresis loops demonstrate the paramagnetic (PM) behavior for the tested manganite compound, where BaMn1−xNixO3 possesses paramagnetic phases and increment of Ni-content affects the magnetic parameters as Ms, remnant Mr, Hc, and magnetic moment nB. Hc increases to 2%; inversely, Ms decreases to 2%, increasing Ni-90%. The attractive electromagnetic properties suggest that BaMn1−xNixO3 could be a promising potential material in the fabrication of magnetic devices on an industrial scale. [ABSTRACT FROM AUTHOR]

Effects of Sc substitution on metamagnetic transitions for erbium are investigated for Er1−xScx ($0.0\le x \le0.2$) to find optimal magnetocaloric materials for high-efficient magnetic refrigeration using static bias magnetic field. We observed that the Néel temperature decreases with increasing $x$. The magnetocaloric properties are discussed in comparison with the previously reported phase diagram. We found that the metamagnetic transitions from the antiferromagnetic-like configurations to the ferromagnetic-like ones are accompanied with relatively large magnetic entropy changes for all the samples. The obtained knowledge would be helpful to further study on magnetic refrigeration utilizing the features of metamagnetic transitions. [ABSTRACT FROM AUTHOR]

Here, we present a process for the fabrication of arrays of anisotropic flexible bonded micro-magnets attached to a transparent base. The micro-magnets are based on hard magnetic SmFeN or Sr-ferrite powders mixed with polydimethylsiloxane (PDMS). The size, shape, and distribution of the micro-magnets are defined using a Si-mold fabricated by deep reactive ion etching (DRIE). The volume fraction of the magnetic powder was fixed at 30% while the thickness of the micro-magnets ranged from 50 to $300~\mu \text{m}$ and their in-plane dimensions from 20 to $400~\mu \text{m}$. Powder alignment was achieved using a bulk NdFeB magnet. Arrays of micro-pillars of height $300~\mu \text{m}$ and width tapering from $300~\mu \text{m}$ at their base to $200~\mu \text{m}$ at their top were characterized using a vibrating sample magnetometer (VSM) and a scanning Hall probe microscope (SHPM) and the results of the latter were compared with analytical simulations. The homogeneous magnetic field produced by a three-axis electromagnet was used to move the micro-pillars in a controlled fashion. The field induced in-plane displacement of the SmFeN-based pillars was more than three times greater than that of the Sr–ferrite-based ones, reaching $13~\mu \text{m}$ at the maximum applied field value of 100 mT. [ABSTRACT FROM AUTHOR]

Magnetization studies were carried out for Tb–Co thin films and Tb–Co/FeNi bilayers, prepared by magnetron sputtering technique. The composition of the Tb–Co films varied in the range of 19–24 at.%. All Tb–Co films were found to have perpendicular magnetic anisotropy in a wide temperature range. In addition, for some Tb–Co films, a spin reorientation transition was observed in the investigated temperature range. An analysis of the obtained results suggests that, in the course of deposition of the FeNi layer onto the Tb–Co layer, an interlayer magnetic boundary is formed, and its parameters depend on the composition of the Tb–Co layer. The magnetic structure peculiarities of this boundary determine the value of the exchange bias in Tb–Co/FeNi bilayers and its temperature dependence. [ABSTRACT FROM AUTHOR]

In this article, the balanced bidirectional-magnetization effect of a newly developed hybrid-magnet-circuit variable-flux memory machine (HMC-VFMM) is revealed and investigated. First, the machine topology and variable-flux principle of the HMC-VFMM are described. In addition, the balanced bidirectional-magnetization effect is analytically unveiled by using a Fourier-series-based hysteresis model of low coercive force (LCF) magnet. The PM magnetization characteristics are then investigated by a coupled solution, which is employed to identify the mismatch between the LCF magnet movement trajectories subject to either continuous one-way or bidirectional alternate current pulses. Finally, a prototype is manufactured and tested to verify the theoretical analyses. [ABSTRACT FROM AUTHOR]

The spin Hall magnetoresistance (SMR) of Pt/FeCoB bilayers with in-plane magnetocrystalline anisotropy was analyzed with respect to a second-order effect in the sensing current, which acts, through the spin Hall effect in Pt, as a torque on the magnetization of the ferromagnetic (FM) layer and changes slightly its configuration. This leads to a small current-dependent shift of the SMR curves in field that allows, in structures with a multidomain state (e.g., Hall bars), the determination of the sign of the magnetic remanence. The SMR measurements were performed as a function of the Pt thickness and the spin Hall angle, and the diffusion length and the field-like and damping-like spin–orbit-torque (SOT) efficiency were determined. The results were compared with the values obtained from harmonic Hall voltage and SOT-FM resonance (FMR) measurements and show a good agreement. [ABSTRACT FROM AUTHOR]