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We investigate the magnetic properties of La2/3Sr1/3MnO3 (LSMO) membranes released from an SrTiO3 (STO) substrate by selectively etching an Sr4Al2O7 sacrificial buffer layer. The magnetic moment and Curie temperatures (TC) of the released LSMO membranes improve significantly over their substrate-bound counterparts. We attribute these enhancements to suppressing strain and oxygen octahedral rotations that are present in substrate-bound films. Moreover, comparing the magnetic hysteresis loops obtained with magnetic fields applied along several crystallographic orientations demonstrates enhanced (weakened) perpendicular (in-plane) magnetic anisotropy in the released LSMO membranes. Our results contribute to potential applications of released LSMO membranes toward flexible spintronics devices, where high spin polarization and TC are desired. [ABSTRACT FROM AUTHOR]

This manuscript presents a model and simulation of the copper chalcopyrite semiconductor CuGaSe2 in order to predict its magnetic properties. In the semiconductor material CuGaSe2 (CGS), the atom Cu is the only magnetic element with a magnetic moment value S = 1/2. We propose a Hamiltonian to calculate the energies corresponding to different configurations of the system. In a first step, we presented the magnetization behavior by using the Monte Carlo simulations (MCS). The magnetizations as a function of the temperature, the exchange coupling have been studied and discussed. We have also deduced and studied the magnetic susceptibilities. To complete this study, we have established and discussed the magnetic hysteresis loops of the studied compound. Finally, we have calculated the corresponding critical exponents and compared them with the standard 3D Ising model. [ABSTRACT FROM AUTHOR]

In the present work a computational approach is applied to model and predict the results of X‐ray resonant magnetic reflectometry – a non‐destructive synchrotron‐based technique to probe chemical composition, crystallographic environment and magnetization in multilayer epitaxial heterostructures with nanoscale depth resolution. The discussed 2D mapping approach is a step forward with respect to conventional resonant X‐ray reflectometry and consists of collecting a fine step array of reflected intensity as a function of grazing angle and photon energy across the absorption edge of a particular chemical element. With the use of circularly polarized photons the method can be extended to magnetic systems to produce a map of dichroic reflectance directly related to the magnetization profile of the heterostructure. Studying the magnetic field dependence of dichroic reflectance maps can provide valuable information on the magnetization reversal of individual sublayers of a multilayer heterostructure. In the present paper modeling is performed for a bilayer system mimicking the behavior of a 30 nm ϵ‐Fe2O3 thin film that is known to exhibit a pronounced two‐component magnetic hysteresis. A technique to find optimal energy/angle combinations in order to sense magnetization of individual sublayers is proposed. Also discussed is the advantage of heavy‐element capping, which leads to a substantial increase of the dichroic intensity oscillation contrast in the pre‐edge region where the sensitivity to the magnetic behavior of the deeply buried interfaces is most pronounced. [ABSTRACT FROM AUTHOR]

In the current work, the effect of nano-sized Sn (50 nm)/Sr partial replacement on the superconducting properties such as crystal structure, quality of intra- and intergrain boundary coupling, dc electrical resistivity, and dc magnetization in the Bi-2212 ceramic superconductors were investigated. Ceramic superconductors with nominal composition of Bi2Sr2-x(Sn)xCa1Cu1.75Na0.25Oy where x = 0.25, 0.30, 0.35 and 0.40 were prepared by solid-state reaction method and characterized by powder X-ray diffraction (XRD), dc electrical resistivity, scanning electron microscopy (SEM) and magnetic hysteresis (M–H) measurements. Phase examination of by XRD indicated that the doping of x = 0.25 ratio nano-sized SnO2 to the strontium sites improved the formation of the Bi-2212 high-temperature superconducting phase. SEM micrographs showed that the morphological structure of all samples consisted of plate-like grains, which were separated from each other by grain boundaries, indicating the Bi-2212 superconducting phase. The highest superconductivity transition temperature among the samples was measured as the Tconset = 86 K at x = 0.25 in Bi2Sr2-x(Sn)xCa1Cu1.75Na0.25Oy. M–H loops of the Bi2Sr2-x(Sn)xCa1Cu1.75Na0.25Oy sample at x = 0.25 ratio is larger compared to other examples, indicating improvement intergrain connectivity as well as enhanced flux pinning centers. In addition, the critical current (Jc) values of the samples were calculated from M–H measurement using Bean's critical current model. The best Jc values were obtained as 570 A/cm2 at 15 K, which is a relatively high value for BSCCO superconductors with polycrystalline structure. [ABSTRACT FROM AUTHOR]

As a typical intelligent device, magnetorheological (MR) dampers have been widely applied in vibration control and mitigation. However, the inherent hysteresis characteristics of magnetic materials can cause significant time delays and fluctuations, affecting the controllability and damping performance of MR dampers. Most existing mathematical models have not considered the adverse effects of magnetic hysteresis characteristics, and this study aims to consider such effects in MR damper models. Based on the magnetic circuit analysis of MR dampers, the Jiles–Atherton (J-A) model is adopted to characterize the magnetic hysteresis properties. Then, a weight adaptive particle swarm optimization algorithm (PSO) is introduced to the J-A model for efficient parameter identifications of this model, in which the differential evolution and the Cauchy variation are combined to improve the diversity of the population and the ability to jump out of the local optimal solution. The results obtained from the improved J-A model are compared with the experimental data under different working conditions, and it shows that the proposed J-A model can accurately predict the damping performance of MR dampers with magnetic hysteresis characteristics. [ABSTRACT FROM AUTHOR]

Traditional circulators utilize ferrites with low magnetocrystalline anisotropy driven by external magnetic bias fields. Hexagonal ferrites with a strong uniaxial anisotropy enable self-biased circulators, significantly reducing their volume, weight, and cost. Here, a unique uniaxial hexaferrite, Cu 18H hexaferrite, with narrow ferrimagnetic resonance (FMR) linewidth at zero magnetic bias field is reported. The temperature-dependent magnetic hysteresis loops show a significant decrease in coercivity from cryogenic to room temperature, indicating a transition from the hard to soft magnetic state. The crystallographic texture ensures a squareness ratio greater than 0.65 and leads to a strong internal bias field induced by the aligned easy-magnetization axes. Owing to the highly dense and oriented crystallites, the zero-field FMR exhibits excellent linewidths of ∼270–320 Oe, which are lower than those of most hexaferrites reported at the K a -band. These results reveal the great potential of Cu 18H hexaferrite as a low-loss microwave ferrite used for self-biased circulators. [ABSTRACT FROM AUTHOR]

The mixed-valence perovskite manganites attracted much attention because of their interesting electro-magnetic properties, and strain modulation on magnetic properties of perovskite manganites is worth exploring. In this paper, [La 0. 8 Ca 0. 2 MnO3/La 0. 5 Ca 0. 5 MnO3] 2 0 superlattice films with different La 0. 8 Ca 0. 2 MnO3 layer thicknesses are prepared by pulsed laser deposition (PLD). The crystal structures (lattice constants) of samples are measured by X-ray diffraction (XRD). The strain of the films is determined according to their crystal structures. The magnetic hysteresis loops (M-H loops) and magnetization versus temperature (M-T) curves of these superlattice films are measured by the physical property measurement system (PPMS). From the M-H loops, the coercive field (H C) of the samples can be measured. From the M-T curves, the Curie temperature (T C) of the samples can be obtained. All samples show a ferromagnetic to paramagnetic transition at TC, and the [La 0. 8 Ca 0. 2 MnO3/La 0. 5 Ca 0. 5 MnO3] 2 0 sample with the La 0. 8 Ca 0. 2 MnO3 layer thicknesses of 72 Å has an antiferromagnetic Néel transition at TN. According to the strain state and magnetic phases, the magnetic properties are comprehensively analyzed. It is found that with the increase of ferromagnetic La 0. 8 Ca 0. 2 MnO3 layer thickness, the ferromagnetic phase is increased, and the double exchange effect can also be enhanced, resulting in the increase of TC. When the thickness of La 0. 8 Ca 0. 2 MnO3 reaches 96 Å, the uneven strain distribution in the superlattice can induce the reduction of ferromagnetic phase compared with antiferromagnetic phase (even antiferromagnetic phase starts to appear), and the double exchange effect can be weakened, and finally leading to the decrease of TC. In addition, with increasing the La 0. 8 Ca 0. 2 MnO3 layer thickness, HC gradually decreases. The change of HC is related to strain states and magnetic phase interactions in the samples. The analysis of the strain and magnetism can contribute to the understanding of perovskite manganite superlattice films. [ABSTRACT FROM AUTHOR]

The 20-nuclearity compound [Fe8Dy12(tea)8(teaH)12(NO3)12]·8MeCN (where teaH3 = triethanolamine) was synthesised and characterised through single crystal X-ray diffraction and magnetic measurements. The shape of the magnetic hysteresis in the microSQUID measurements was rationalised using the MAGELLAN program. [ABSTRACT FROM AUTHOR]

Gadolinium-doped cerium oxide (Ce 0.9 Gd 0.1 O 2-∂ ; CGO) and strontium-doped lanthanum ferrite (La 0.6 Sr 0.4 FeO 3 ; LSF) are well-known compounds for their application in solid oxide fuel cells, dense oxygen permeable membrane, and high-temperature ceramic reactor. The superior electro-catalytic performance of these two individual oxides or their composites is well established as it originates from multivalent cations (Ce3+/4+ and Fe2+/3+/4+) and doping-induced defects like electrons, holes, and oxygen vacancies. This work focuses on synthesizing and characterizing composite taking CGO and LSF in different weight ratios, i.e., 10:90, 30:70, 50:50, 70:30, and 90:10 by sol-gel auto-combustion process. End members CGO and LSF were also synthesized for comparison purposes. All synthesized nanopowders (single phases and their composites) were characterized with X-ray diffraction (XRD) for phase identification and Scanning electron microscopy (SEM) for elemental composition analysis. XRD and SEM results established the formation of the required phase and targeted composition. The optical properties of the materials were evaluated with the help of ultraviolet–visible Diffuse Reflectance Spectroscopy (UV–Vis DRS). Tauc's approximation measured band gap energies, and all the composites showed a very high band gap in the 4.85–5 eV range. Magnetic properties such as saturation magnetization (M s), remanence (M r), and coercive force (H c) were calculated from a magnetic hysteresis loop obtained from the Vibrating-sample magnetometer (VSM) experiment at room temperature. Furthermore, the law of approach to saturation (LAS) model was applied to more precisely calculate M s and other essential parameters. In magnetic characterization, the LSF phase fraction controls the overall magnetic property of the composites. Electrochemical behavior, such as the composites' charge storage ability and stability were tested by cyclic voltammetry and chronopotentiometry method. All the samples exhibited good stability, and the highest specific capacitance of 26 F/gm was obtained for the composite sample (CL91) when only 10 % LSF phase was incorporated in the nanocomposite. [ABSTRACT FROM AUTHOR]

Spin valves with a synthetic antiferromagnet were fabricated via magnetron sputtering. It was shown that the fabricated spin valve layers had a perfect microstructure and smooth interfaces, and therefore, an RKKY interaction dominated in the coupling of the ferromagnetic layers separated by a copper spacer. Rhombus-shaped micro-objects were fabricated from a single spin valve film. The thermomagnetic treatment procedure was found to form unidirectional anisotropy in the micro-object such that the values of the exchange bias fields in the rhombus' nonparallel sides were opposite in sign. For the CoFeNi/Ru/CoFeNi synthetic antiferromagnet, we determined the differences between the ferromagnetic layer thicknesses at which the thermomagnetic treatment formed the same exchange bias all over each rhombus' side. We also fabricated a sensor element in which each side of the rhombus was the shoulder of a Wheatstone bridge. After the thermomagnetic treatment procedure, each shoulder worked as an active magnetosensitive element, enabling the device to operate as a full Wheatstone bridge. The sensor output exhibited a step shape, high sensitivity to field changes, and significant magnetic hysteresis. Such characteristics are suitable for switching devices. [ABSTRACT FROM AUTHOR]

Despite being essential in determining absolute paleomagnetic field intensity (API) with high fidelity over Earth science research topics, API determination still suffers little quantitative success. This is due to common nonideal magnetic behaviors in experiments using natural rocks caused by physiochemical changes in the magnetic minerals contained. Although linking rock-magnetic parameters to API results may be fundamental, negligible effort has been made using the Tsunakawa–Shaw (TS) API method despite its potentially high experimental success rate in overcoming nonideal magnetic effects. Here, we explore the relationships between rock-magnetic parameters retrieved using relatively rapid and widely pre-conducted measurements and TS API results from late Cenozoic basaltic rocks. We selected rock-magnetic parameters quantified from strong-field high-temperature thermomagnetic curves, magnetic hysteresis loops, and back-field isothermal remanent magnetization demagnetizations. We provide new data pairs of rock-magnetic parameters and TS API results for 41 basaltic rock samples from 8 sites (cooling units) in Northeast China. Then, by compiling them with published data of similar quality, we compiled 133 pairs of rock-magnetic and TS API data at the sample level (38 sites). Using this data compilation, the following topics of interest were identified: Magnetic coercivity (Bc) and remanence coercivity (Bcr) among the hysteresis parameters, and the thermomagnetic parameter ITC|m| (an index of thermal change quantifying an average of the differences in saturation magnetization at a full temperature range of during a single heating–cooling run) allow meaningful and efficient discrimination between data subsets divided by "success" or "failure" in the API results. We propose sample preselection criteria for the TS experiment: a minimal set of Bc ≥ 13 mT (or Bcr ≥ 26 mT) and ITC|m|≤ 0.15. Moreover, extended consideration based on the preselection criteria may allow the screening of potentially biased specimen/sample-level API estimates in the site-averaged determination of such a site with a large within-site API dispersion. [ABSTRACT FROM AUTHOR]

Magnetic fields in transformer cores are typically assumed to be one-dimensional fields, thus allowing magnetization processes to be regarded as axial magnetization. However, in the core corners or T-joint points of medium- and high-power rating transformers, the magnetic lines have different directions with respect to the rolling direction. This paper describes a method that allows changes in the flux density of transformer steel sheets to be calculated for any magnetization direction. These changes are assumed to depend only on certain limiting hysteresis loops assigned separately to the rolling and transverse directions of a tested transformer sheet, where these loops depend on the magnetization direction on the sheet plane. The selection of coefficients that define the limiting hysteresis loops for several magnetization directions is described, and the condition for the flux density saturation is considered. The resultant flux density in a specified magnetization direction is the geometric sum of the corresponding flux densities assigned to both the rolling and transverse directions. The limiting and partial hysteresis loops determined based on the proposed method for several magnetization directions are compared with analogous measured loops. Additionally, a comparison of the calculated hysteresis loops with loops showing changes in the resultant flux density for several magnetization direction is presented. [ABSTRACT FROM AUTHOR]

The formulation of polymer with embedded magnetic nanoparticles results in promising nanocomposites for smart and analytical applications. Nanocomposites containing polyacrylonitrile (PAN) and different mass contents of strontium hexaferrite (SFO) were prepared using the casting method. The nanocomposite samples were characterized by using different techniques such as field-emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction, differential scanning calorimetry, and thermogravimetric analysis. Dielectric investigations of SFO/PAN nanocomposites showed that the permittivity and conductivity are considerably enhanced as the content of SFO increased. Optical properties revealed that the absorption and transmittance spectra were significantly affected by adding SFO nanoparticles to the PNA polymer matrix. To investigate the magnetic properties of the nanocomposite samples, the vibrating sample magnetometer was used. The magnetic hysteresis loops illustrated the ferromagnetic nature of SFO/PAN nanocomposites. Different magnetic parameters were given, and they depend on the content of PAN in the nanocomposites. [ABSTRACT FROM AUTHOR]

The magnetic and magnetocaloric properties of a zigzag triangular nano-graphene with Ruderman-Kittel-Kasuya-Yosida (RKKY) exchange interactions in the mixed 1 and 3/2 spins are studied with the aid of the Monte Carlo investigations. The thermal magnetizations and the magnetic susceptibilities are considered. The phase diagram of the system and the variation of magnetizations with crystal field are established. The magnetic entropy for different external magnetic fields has been also sketched. The dependence of the field on the relative cooling power (RCP) of the system is found; the specific heat displacement of the system is displayed. Also, the adiabatic temperature of the system has been defined. Lastly, the magnetic hysteresis cycle with mixed spins S = 1 and σ = 3/2 for several different parameters is obtained. It can be observed that the values obtained for RCP rise with increasing external magnetic field and reduce with increasing N for constant parameters. The critical temperature values are also affected by the increasing number of non-magnetic layers. In addition, the effect of the RKKY interaction decreases as 1/N2. As a consequence, the system becomes rapidly out of order as the number of non-magnetic layers N is increased. [ABSTRACT FROM AUTHOR]

In this paper, the Preisach model for magnetic hysteresis of grain-oriented silicon steel under PWM excitation is improved. First, an improved Preisach model for the magnetic hysteresis of grain-oriented silicon steel under PWM excitation is proposed. Second, the experimental platform for grain-oriented silicon steel sheets under PWM excitation is established. Finally, by comparative analysis, it is concluded that the error of the improved model is far less than that of the classical model (the error here refers to the discrepancy between experimental results and theoretical model predictions). The improved model is 1.4% to 9% more accurate than the classical model. A more accurate model can provide more accurate material parameters for the calculation of the magnetic field in the transformer core, which is of great significance to the production and design of the transformer. [ABSTRACT FROM AUTHOR]

In order to develop the building blocks for future biosensing and spintronic applications, an engraving technique using electron beam lithography is employed in order to develop nanomagnetic pre-patterned structures with logic potential. The paper describes the realization and morphological and magnetic characterization of potentially logic-conditioned substrates, a building block to be further used as an integration platform upon which nanodevices, such as magnetic wires, or various geometrical shapes, circles, triangles, can be considered as pre-requisite for full integration into logic devices. As a proof of concept, regular arrays of FePt circles or magnetic dots were devised and structural characterization by X-ray diffraction and transmission electron microscopy proved the occurrence of the tetragonal L10 phase. Moreover, the magnetic characterization provided more insight into the potential of such arrays of magnetic devices as the hysteresis provided good values of magnetic coercivity, remanent and saturation magnetization. These findings show good potential for developing regular arrays of uniformly shaped magnetic entities with encouraging magnetic performances in view of potential applications in various applications. [ABSTRACT FROM AUTHOR]

Skyrmions are vortex‐like localized magnetic structures that possess an integer‐valued topological index known as the skyrmion number or topological charge. Skyrmion number determines the topology‐related emergent magnetism, which is highly desirable for advanced storage and computing devices. In order to achieve device functions, it is necessary to manipulate the skyrmion number in confined nanostructured geometries using electrical methods. Here, the reliable current‐controlled operations for manipulating the skyrmion number through reversible topological transformations between skyrmion chains and stripe domains in confined Fe3Sn2 nanostripes are reported. The results of micromagnetic simulations are successful in numerically reproducing the experiments and explaining them through the combined effect of current‐induced Joule heating and magnetic hysteresis. These findings hold the potential to advance the development of topological spintronic devices. [ABSTRACT FROM AUTHOR]

Tetravalent titanium substituted lithium zinc manganese ferrite having chemical formula Li0.35+x/2Zn0.1Mn0.1TixFe2.35 − 3x/2O4 where x = 0.00, 0.15, 0.30, 0.45, 0.60, 0.75 were prepared by using the solid-state ceramic technique. Using additives V2O5 and Na2SiO3 as sintering aids, the samples were calcined and sintered at 900 °C and 950 °C, respectively for 1 h each, at a regulated heating rate of 10 °C/min. The X-ray diffraction (XRD) studies showed a single-phase spinel structure. XRD data were used to assess the structural information including density, lattice constant, and crystallite size. The additives reduced the sintering temperature and time and an increase in porosity has been observed with the increase of Ti4+ substitution. Scanning electron microscopy (SEM) was used to analyze the samples' microstructure, while Energy-dispersive X-ray (EDAX) analysis was used to identify the different elemental makeup. The fluctuation of the initial permeability and permeability loss at room temperature with a change in frequency was investigated using an impedance analyzer and found that higher substitution reduced the resonance frequency. The magnetic hysteresis studies showed that saturation magnetization reduced with an increase of Ti4+ substitution. The results obtained were analyzed and discussed systematically in the paper. [ABSTRACT FROM AUTHOR]

Continuous monitoring of the prestressed members of a bridge under construction using the free cantilever method (FCM) is crucial for ensuring bridge safety. Temperature-sensitive sensors require special considerations as they may misinterpret the signal and tension. Moreover, the unnecessary and inappropriate use of features obtained from the sensor signal can deteriorate the efficiency of the signal and, therefore, tension analysis. This study proposes a tension estimation method using an embedded elastomagnetic (EM) sensor with a temperature-compensation technique. Changes in the signal due to the tension in the temporary steel rods were analyzed using a full-scale test, and the sensor data were acquired for 15 months via the field application. The temperature effect on the signal could be removed by subtracting the tension from the signal using the thermistor data, reducing the error by 91.99% when considering permeability. Additionally, linear regression (LR) and machine learning (ML) algorithms were adopted to predict the tension. Furthermore, the performances of both algorithms were compared using mean absolute error (MAE) and R2. For the prediction using each feature in magnetic hysteresis, LR surpassed ML and the permeability exhibited the highest prediction performance. Meanwhile, predictions using multiple features were attempted to investigate the applicability of ML. Two cases of prediction were performed using ML: on using all the features and the other using three features excluding coercivity, which showed poor relevance to tension. As a result, the performance of the tension prediction was improved significantly compared to the results obtained by LR. In summary, the obtained results have demonstrated that the utilization of selective features of data with temperature compensation techniques could enhance predictive power. [ABSTRACT FROM AUTHOR]

Bismuth ferrite is a prominent candidate for spintronic application if its multiferroic nature is improved. A chemical technique has been used to synthesize BiFe1–xAlxO3 (x = 0, 0.02, 0.04, 0.06, 0.08) samples. Structural and microstructural properties of the synthesized compound have been studied from X-ray diffraction data. The dielectric nature of all the samples has been studied by measuring impedance at various frequencies. The ferroelectric nature of all the samples has been studied using P–E data. Magnetic hysteresis data has been obtained to study the ferromagnetic nature of the samples. Improved multiferroic behaviour has been found after Al doping at the Fe site of BiFeO3. [ABSTRACT FROM AUTHOR]

Composite magnetic nanostructures are a subject of high research interest, as they provide a number of exciting effects absent in live nature. Among others, much attention has been paid to the studies of exchange coupling in antiferromagnetic/ferromagnetic (AFM/FM) films, which leads to the pinning effect. It manifests itself as a widening and shift of the magnetic hysteresis loop with respect to zero value of the external magnetic field oriented along the pinning direction. In this work, we report on comparative studies of linear and nonlinear magneto-optical effects under the laser-induced switching of the pinning effect in IrMn/CoFe films of various thickness of the ferromagnetic CoFe layer. We found that the magneto-optical response of the pinned AFM/FM nanofilms appears with different hysteresis loop parameters in the transverse magneto-optical Kerr effect (MOKE) and interface-sensitive magnetization-induced second harmonic generation (SHG), indicating the diversity of the magnetic effects at interfaces compared to the bulk of the films. [ABSTRACT FROM AUTHOR]

In recent years, multiferroic (MF) materials have attained remarkable attention because of their exceptional ability to demonstrate both ferroelectric (FE) and magnetic properties simultaneously which has lead to their applications in memory, sensors, and energy storage devices. Here, a simple synthesis approach is used to enhance the ferroelectricity and induce the multiferroicity in double transition metal carbide (DTM) MXene film. The successful synthesis is confirmed by X‐ray Diffraction (XRD), Raman Spectroscopy, and Scanning Electron Microscopy (SEM) analysis. In addition, the FE and magnetic hysteresis (MH) loops are conducted to observe the nature of synthesized materials. Furthermore, the magnetoelectric (ME) effect is also examined to explore its significance in data storage and ME signal generation devices. Thus, the findings reveal the first report on the co‐existence of FE and magnetic properties of DTM MXene for potential applications in nano‐electronic devices of future technology. [ABSTRACT FROM AUTHOR]

This study investigates the impact of annealing and magnetization on the magnetostrictive behavior of pure nickel, which is used as the core of an ultrasonic transducer. Pure metals are not commonly used as magnetic materials due to their limited magnetic and non-magnetic properties. Analyzing the effects of alloying on different characteristics of pure elements is a complex process. Improving the efficiency of magnetostrictive transducers by enhancing their properties is an area of interest for researchers. Grain size, in particular, is a significant parameter that affects the properties of ferromagnetic materials. This study reveals that exposing pure nickel and magnetized samples to an electro-polishing solution with 10 % oxalic acid for 60 s results in the appearance of grain boundaries. Furthermore, the study finds that the 90° domain wall energy is higher than the 180° domain wall energy, impacting the radial magnetostrictive force more than the longitudinal magnetostrictive force. The results show that annealing reduces the maximum output magnetic hysteresis, while magnetization has little effect. Additionally, annealing significantly reduces the coercive field, increasing the magnetostriction effect. Therefore, annealed nickel is a promising candidate for use as the core of an ultrasonic transducer for removing residual chemicals from fruits and vegetables.

This study investigates the application of soft magnetic composite (SMC) materials in alternator core manufacturing for bladeless wind turbines operating under the principle of vortex-induced vibration (VIV), employing additive manufacturing (AM) technologies. Through a comparative analysis of alternator prototypes featuring air, SMC, and iron cores, the investigation aims to evaluate the performance of SMC materials as an alternative to the most commonly used material (iron) in VIV BWT, by assessing damping, resonance frequency, magnetic hysteresis, and energy generation. Results indicate that while alternators with iron cores exhibit superior energy generation (peaking at 3830 mV and an RMS voltage of 1019 mV), those with SMC cores offer a promising compromise with a peak voltage of 1150 mV and RMS voltage of 316 mV, mitigating eddy current losses attributed to magnetic hysteresis. Notably, SMC cores achieve a damping rate of 60%, compared to 67% for air cores and 59% for iron cores, showcasing their potential to enhance the efficiency and sustainability of bladeless wind turbines (BWTs). Furthermore, the adaptability of AM in optimizing designs and accommodating intricate shapes presents significant advantages for future advancements. This study underscores the pivotal role of innovative materials and manufacturing processes in driving progress towards more efficient and sustainable renewable energy solutions.

This paper proposes an advanced approach to construct static hysteresis loop of Grain-Oriented (GO) electrical steels for dynamic modeling and energy loss analysis. The proposed approach is in line with the magnetic hysteresis and phenomenological concepts of rate-dependent and rate-independent energy loss components of ferromagnetic materials under time-varying magnetic fields. The proposed method can predominantly describe energy loss mechanism and magnetization processes of the material. Accuracy of this technique was validated on Epstein size laminations of 3% GO silicon steels. The results explicitly confirmed the effectiveness of the proposed method in dynamic hysteresis modeling of GO electrical steels at magnetizing frequencies up to 1 kHz and peak flux densities up to 1.7 T. [ABSTRACT FROM AUTHOR]

Co2Fe2O4 NPs were made using the sol‐gel ignition technique employing citric acid (C6H8O7.6H2O) as a reducing agent to oxidizing agent with a ratio of 1 : 3. A thorough study of the effects of divalent Zn2+ and trivalent Y3+ ion on their structural, Infra‐red, morphological, magnetic, DC‐electrical, optical, and photocatalytic activity. All of the samples have crystallized to a cubic spinel structure with a single phase space group Fd3m, according to the analysis of the XRD pattern consisting of the intense reflections (220), (311) (222), (400), (422), (511), (440), (533), and (444). Transmission electron microscopy (TEM) suggested the particle size range of ~27 nm; and demonstrates the agglomerations on the tip of MNPs, which are ideal for increasing surface area, and infrared study verifies the spinel structure. With a decrease in the hysteresis loop for the Zn−Y ligand, the magnetic hysteresis loops demonstrate a ferrimagnetic character. With Zn−Y, magnetic characteristics are noticeably affected; saturation magnetization (Ms) 70.9133 to 59.2148 emu/g; and coercivity (Hc) 1900.30 to 193.96 Oe both exhibit a decrease. The DC‐electrical resistivity image reveals the CFMNPs′ semiconducting nature and the optical energy bandgap demonstrates a decrease from their original state. The MB dye's decolorization demonstrates the amazing deterioration in a short amount of time 20 to 80 minutes range was observed to be 35.88, 61.92, 76.40, and 94.07 %. [ABSTRACT FROM AUTHOR]

Zn 0.35 Co 0.05 Ni 0.60- x Mg x Fe 1.96 O 4 ferrites (x = 0, 0.08, 0.16, 0.24, 0.32, 0.40) were prepared via a solid-state reaction. The phase composition and microstructure of the ferrite powders were analysed and the samples were determined to be pure spinel ferrites. At x = 0.24, the volume loss (P CV) of this ZnCoNiMg ferrite was as high as 829.23 mW/cm3. An increase in the amount of Mg substitution decreased the density of the ferrite sample, resulting in a larger P CV. Analysis of the magnetic hysteresis (M − H) loops revealed that ZnCoNiMg ferrites had the distinct magnetic properties of a soft magnetic ferrite. When x = 0.24, the reflection loss of this ZnCoNiMg ferrite sample had a minimum value of −36.713 dB under certain conditions. The more single domain particles, the more electromagnetic energy absorbed by ferromagnetic resonance effect. Based on these magnetic properties and absorption properties, the ZnCoNiMg ferrites have excellent potential for absorbing electromagnetic energy and are suitable for fabricating wave-absorbing materials. [ABSTRACT FROM AUTHOR]

The synthesis, single-crystal structures and magnetic properties of two new double-zigzag-chain cyano-bridged heterobimetallic {[MII(Py-NOH)2][FeIII(Tp*)(CN)3]2}·H2O ([Fe III2 MII]) (Py–NOH = 4-pyridinealdoxime, Tp* = tris(3,5-dimethylpyrazol-1-yl)borohydride, M = Ni (1), Fe (2)) compounds are reported. The crystal structures of both compounds were determined by single-crystal X-ray diffraction. Complexes 1 and 2 are isostructural, with the crystal structure comprising neutral double-zigzag (4,2-ribbon-like) bimetallic chains. The FeIII ion is coordinated by three cyanide carbon atoms and three nitrogen atoms of Tp* anions. However, the MII ion is surrounded by four cyanide nitrogen atoms and two nitrogen atoms from two Py-NOH ligands. The crystal structures and magnetic studies demonstrate that both complexes behave as single-chain magnetics (SCMs) with intrachain ferromagnetic coupling. Furthermore, [Fe III2 NiII] exhibits an excellent coercive field of 0.42 T at 1.8 K, among cyano-bridged 3d transition-metal-based SCMs reported thus far. Preliminary theoretical calculations provide a deep understanding of the magnetic properties of [Fe III2 NiII]. [ABSTRACT FROM AUTHOR]

According to this study, Co 2 Z ferrite is suitable for applications in high-frequency antennas. Ba 3 Co 2 Fe 24-x Dy x O 41 samples with different values of Dy3+ doping concentration (x) in the range of 0.00–0.25 were prepared in the study by employing solid-state sintering and 2.5 wt% Bi 2 O 3 sintering aids. A systematic analysis of the physical phase structure, microstructure, and magnetic dielectric properties of the samples was also performed. The X-ray diffraction patterns of the samples showed that doping with Dy3+ ions and the addition of the Bi 2 O 3 sintering aid had not changed the physical structure of the sample material, indicating that the material was still a Z-type hexagonal ferrite. In addition, according to the magnetic hysteresis loops of the samples, all six groups of them exhibited typical soft magnetic properties. With an increase in the Dy3+ ion doping concentration, the saturation magnetization intensity and coercivity of the samples initially increased and then decreased. The sample with a Dy3+ ion doping concentration of 0.15 had the most uniform grain distribution, largest density, and smallest porosity among the samples. Additionally, that sample had the maximum values of the real parts of the magnetic permeability (7.89) and permittivity (13.90) while having a low magnetic loss (tanδ μ ≤0.04) and a low dielectric loss (tanδ ε ≤0.03). Thus, this type of magnetic dielectric materials will have significant potential for use in high-frequency antenna applications. [ABSTRACT FROM AUTHOR]

Based on the Ising model, Monte Carlo simulation (MCS) and the Mean-field approximation (MFA) were used to examine the magnetic properties and the phase diagram of a ferrimagnetic mixedspin (2,3/2) hexagonal Ising nanotube with core-shell structure. The effects of exchange interactions (Jint, Js) and the single-ion anisotropies (Ds, Dc) on the magnetization of the total system, the two sublattices and the hysteresis loops have been discussed in detail. The phase diagrams under the effect of different parameters have been provided. The results demonstrate the emergence of compensation phenomena as well as the second-order phase transitions. Multiple behaviors of hysteresis loop, including single and triple hysteresis loops, were identified as a result of competitions between various parameters. [ABSTRACT FROM AUTHOR]

The numerical modeling of magnetic materials in simulators is a difficult task, above all in real devices with specific excitation. The aim of this work is to compare the accuracy of scalar and vector Preisach models in a well know test benchmark: the TEAM 32 problem. The availability of measured data for this benchmark test and the simple geometry allow us to build hysteresis models and to test them in a 2D finite element analysis (FEA) scheme. The specific numerical formulation of each hysteresis model implemented is described, including the technique for the numerical identification of parameters starting from measured data. The comparison among the models is done in terms of accuracy, but also in terms of easy implementation in the FEA scheme and of computational cost. [ABSTRACT FROM AUTHOR]

Ferromagnetism and superconductivity are two key ingredients for topological superconductors, which can serve as building blocks of fault-tolerant quantum computers. Adversely, ferromagnetism and superconductivity are typically also two hostile orderings competing to align spins in different configurations, and thus making the material design and experimental implementation extremely challenging. A single material platform with concurrent ferromagnetism and superconductivity is actively pursued. In this paper, we fabricate van der Waals Josephson junctions made with iron-based superconductor Fe(Te,Se), and report the global device-level transport signatures of interfacial ferromagnetism emerging with superconducting states for the first time. Magnetic hysteresis in the junction resistance is observed only below the superconducting critical temperature, suggesting an inherent correlation between ferromagnetic and superconducting order parameters. The 0-π phase mixing in the Fraunhofer patterns pinpoints the ferromagnetism on the junction interface. More importantly, a stochastic field-free superconducting diode effect was observed in Josephson junction devices, with a significant diode efficiency up to 10%, which unambiguously confirms the spontaneous time-reversal symmetry breaking. Our work demonstrates a new way to search for topological superconductivity in iron-based superconductors for future high Tc fault-tolerant qubit implementations from a device perspective. The authors study Josephson junctions where the superconductors are Fe(Te,Se) flakes and the weak link is just a 0.36 nm van-der-Waals gap between the two stacked flakes. They report global device-level transport signatures of interfacial ferromagnetism. [ABSTRACT FROM AUTHOR]

Pure electric field-controlled 180° magnetization switching plays a vital role in low-power magnetoelectric memory devices. Using micromagnetic simulation, we engineered a square-shaped epitaxial Fe3Si nanomagnet on a PMN-PT piezoelectric substrate to make the magnetic easy axis slightly deviate 18° from the piezostrain axis, aiming to break the symmetry of the magnetization distribution and achieve deterministic magnetization reversal paths. Under the coaction of a magnetic field and an electric field, the simulated magnetic hysteresis loops and magnetic domain patterns reveal a fourfold to twofold magnetic anisotropy transition and magnetization reversal paths. Stimulated by pure electric field-induced piezoelectric strain, deterministic 180° magnetization reversals are accomplished by the two successive clockwise 90° switching process. The results help to comprehend electrically regulated deterministic magnetization reversal and pave an avenue for designing multistate spintronics devices. [ABSTRACT FROM AUTHOR]

In this paper, we studied the magnetism of Fe2N, using the ab initio and Monte Carlo studies. The magnetic moment and the exchange couplings are deduced by ab initio calculations. The obtained density of states is not symmetrical with respect to the axis of energy proving the ferromagnetic character of this compound. Any gap energy, at the Fermi level, is found confirming the metallic character of this compound. The Hamiltonian of this system consists of several physical parameters. Both the magnetic entropy and the maximum magnetic entropy are obtained. The relative cooling power and the magnetic hysteresis cycle are illustrated. The transition temperature TC value has been deduced and found to be about 252.01 K. This value is in good agreement with the experimental results presented. Also, we found that the magnetizations decrease rapidly to zero with increasing temperature. This is due to the ferromagnetic-paramagnetic phase transition caused by thermal energy. [ABSTRACT FROM AUTHOR]

The striving for the independence of fossil energy sources by further development of renewable energies as well as the change in mobility act as a driving force on technological innovations. Magnetic materials with improved magnetic efficiency help to push the limits for optimized, low‐loss power conversion applications and electrification. Besides improving the chemical composition, that is, gaining better performance using alloys reduced or free of heavy rare earth elements, microstructure optimization has proven to be a crucial field of research. In order to better control the grain size, phase distribution and texture of the polycrystalline material, new process routes, such as severe plastic deformation, need to be investigated and explored in addition to the state‐of‐the‐art method – sintering. Here, attention must be paid to the possible formation of soft magnetic α‐Fe after the casting process prior to the actual deformation step, as these secondary phases negatively affect the hysteretic behavior of the magnet. Assistance in the analysis of the underlying magnetic mechanisms is provided by micromagnetic theory. Besides the reliable prediction of the magnetization distribution on micron‐scale, especially in a multi‐phase microstructure, it also allows for the analysis of the magnetic hysteresis behavior. This work provides a micromagnetic simulation frame work based on a finite element scheme. Relying on this framework the effective hysteresis behavior of two different heterogeneous microstructures (Nd2Fe14B and Nd2Fe14B/α‐Fe) are analyzed and compared. [ABSTRACT FROM AUTHOR]

The paper presents the results of a comprehensive study of the hysteresis characteristics of Sm Gd Co Cu alloys (), considering their actual microstructure. It is shown that in the as-cast state, all alloys in the series are significantly heterogeneous and contain inclusions of up to three phase components. High-temperature annealing at 1050 C for 4 h enables modifying the microstructure of the original alloys, however, a single-phase state was only achieved for alloy samples with . The high-coercivity state of the samples is provided by a regular microstructure and is implemented through the pinning mechanism. The maximum coercive force of 0.94 T was achieved on the Sm Gd Co Cu composition. [ABSTRACT FROM AUTHOR]

We studied the magnetostriction coefficients, λs, Curie temperature, Tc, and their dependence on annealing conditions in Fe47Ni27Si11B13C2 and Co67Fe3.9Ni1.5B11.5Si14.5Mo1.6 amorphous glass-coated microwires with rather different character of hysteresis loops. A positive λs ≈ 20 × 10−6 is observed in as-prepared Fe47Ni27Si11B13C2, while low and negative λs ≈ −0.3 × 10−6 is obtained for Co67Fe3.9Ni1.5B11.5Si14.5Mo1.6 microwire. Annealing affects the magnetostriction coefficients and Curie temperatures, Tc, of both Fe47Ni27Si11B13C2 and Co67Fe3.9Ni1.5B11.5Si14.5Mo1.6 glass-coated microwires in a similar way. Observed dependencies of hysteresis loops, λs and Tc on annealing conditions are discussed in terms of superposition of internal stresses relaxation and structural relaxation of studied microwires. We observed linear λs dependence on applied stress, σ, in both studied microwires. A decrease in the magnetostriction coefficient upon applied stress is observed for Co-rich microwires with low and negative magnetostriction coefficient. On the contrary, for Fe-Ni-rich microwires with a positive magnetostriction coefficient, an increase in the magnetostriction coefficient with applied stress is observed. The observed results are discussed considering the internal stresses relaxation and short range atomic rearrangements induced by annealing on hysteresis loops, magnetostriction coefficients and Curie temperatures of studied microwires. [ABSTRACT FROM AUTHOR]

Cerium-substituted yttrium iron garnet (Ce:YIG, Ce0.9Y2.1Fe5O12) was epitaxially grown on a (111)-oriented yttrium aluminum garnet (YAG) substrate using radio frequency ion beam sputtering. Magnetic hysteresis loops, transmissivity spectra, and magnetooptical (MO) responses, including Faraday rotation and Faraday ellipticity, were measured. The structural properties of the grown Ce:YIG were characterized using the x-ray rocking curve, reciprocal space map, pole figure, and x-ray reflectivity. X-ray photoelectron spectrometry revealed a dominant Ce3+ state in the grown Ce:YIG, but the transmission electron microscopy images showed columnar growth of Ce:YIG. This study demonstrates integration of epitaxial Ce:YIG on YAG, marking a significant step toward the fusion of MO garnets and laser crystals. [ABSTRACT FROM AUTHOR]

Single crystalline polar magnets (Mn1−xCox)2Mo3O8 (0 ≤ x ≤ 1) have been synthesized, and their magnetic properties have been studied. Magnetic interactions of the samples can be modulated drastically by Co-doping, and a ferrimagnetic to antiferromagnetic phase transition is identified at x = 0.35. For the samples hosting a ferrimagnetic state (0 ≤ x ≤ 0.3), square-like magnetic hysteresis loops are commonly identified, and the remnant magnetization and coercive field are revealed to strongly depend on the Co-content and temperature. The occupation ratio and magnetic nature of Co2+ are key ingredients to dictate the competition of various magnetic exchange couplings in the samples. [ABSTRACT FROM AUTHOR]

The present manuscript portrays environmental benign, cost‐effective and energy efficient green route way to synthesize Mg−Zn ferrite nanoparticles [Mg0.05Zn0.05Fe2O4 NPs] using Ocimum Basilicum leaf extract [OBLE]. X‐ray diffraction (XRD) analysis revealed that Ocimum Basilicum leaf extract mediated Mg−Zn ferrite nanoparticles [OBLE@Mg−Zn NPs] exhibit face centred cubic crystallinity with space group Fd3‾m ${{\rm F}{\rm d}\bar{3}{\rm m}}$ as confirmed by Rietveld refinement studies. Microstructural analysis illustrated uniform surface morphology with well interlinked grain with an average grain size of 35.6±0.12 nm. FTIR spectra showed existence of hydroxyl −OH group at 3403 cm−1 and C=C vibration at 2345 cm−1. Magnetic hysteresis loop (M−H loop) confirmed the superparamagnetic behaviour of OBLE@Mg−Zn NPs. Cytotoxic activity of OBLE@Mg−Zn NPs was carried out against breast cancer cell line MDA‐MB‐231. Dose dependent cell viability of cancerous cells depicted cytotoxic potential of OBLE@Mg−Zn NPs. [ABSTRACT FROM AUTHOR]

The structural, optical, and magnetic characteristics of the (CoFe2O4) x – (BaTiO3)100-x (x = 10, 20, 30, 40, 50) nanocomposites prepared using the sol-gel technique were examined. X-ray diffraction data confirm formation of the tetragonal phase for BTO and the spinel phase for CFO for all composites. The magnetic hysteresis loop measurements were performed using a vibrating sample magnetometer at room temperature. All of the composites had improved ferromagnetic characteristics, which are highly influenced by the amount of the CFO phase. The bandgap energy values decreased as the CFO concentration increased. The dielectric constant, loss function and conductivity for samples were measured. [ABSTRACT FROM AUTHOR]

In this study, the synthesized rare earth Ce3+ ion doped Mg-Ni-Cu ferrites with composition formula Mg0.5Ni0.3Cu0.2CexFe2-xO4 (0.0 ≤ X ≤ 0.1) using solution gel auto-combustion method. Synthesized ferrite samples were systematically investigated for their structural, morphology, optical, and dielectric properties at varying temperatures and magnetic properties at room temperature. X-ray diffraction analysis confirms the formation of the cubic spinel phase with the Fd-3 m space group, and reviled the development of a secondary phase of cerium oxide CeO2 from the cerium concentration was increased to X = 0.04. The FESEM micrographs of our prepared ferrites show the nano-pores surface and spherical shape grains. EDX confirms the presence of all desired elements. FTIR studied supports the XRD finds. UV–vis spectra showing the blue shift along all samples, and Tauc plots giving the highest band gap energy of 2.54 eV were obtained for the X = 0.06 sample, and the lowest for X = 0.02 is 2.38 eV. VSM instrument was adopted to evaluate the magnetic behaviour of our prepared ferrites at room temperature. The magnetic hysteresis loop confirmed the ferromagnetic behaviour. Ce3+ substitution remarkably affected prepared material coercivity, and magnetic saturation was found between 15.22 emu/g and 22.41 emu/g. The squareness ratio of prepared material was found between 0.19 and 0.26, and it is known that the squareness ratio values fall in the range of multi-domine sates (0.05–0.5). Dielectric properties of synthesized ferrites were produced with normal ferrite plots with higher dielectric constant values. Most significantly, observed very low dielectric loss tangent values. The impedance analysis confirms the dominance of grain boundary resistance with only one semi-circle. [ABSTRACT FROM AUTHOR]

Hexagonal ferrites with the formula SrxBa(1−x)Fe12O19 (x = 0; 0.3; 0.5; 0.7; and 1) were prepared using the citrate method. The main feature of this synthesis is a relatively low calcination temperature of 700 °C. An X-ray diffraction study revealed a single-phase material. According to SEM, the particles were 50−70 nm in diameter. The Curie temperature of the samples that were determined using the DSC method varied in a very narrow range of 455−459 °C. Analysis of the magnetic hysteresis loops obtained at 300 K and 50 K indicated all samples as magnetically hard materials in a single-domain state. The maximal magnetic characteristics encompass strontium hexaferrite. The terahertz spectra of complex dielectric permittivity and the spectra of infrared reflectivity were measured at room temperature in the range of 6–7000 cm−1. The obtained broad-band spectra of the real and imaginary parts of permittivity reveal significant changes associated with structural distortions of the (Sr,Ba)O12 anti-cuboctahedron caused by the substitution of Ba2+ with Sr2+ in the same crystallographic positions. [ABSTRACT FROM AUTHOR]

Nickel and samarium-doped strontium ferrite nanoparticles were synthesized using the sol-gel auto-combustion method. The micro-structural characteristics of the ferrite were investigated using X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM). It was determined that the particle size ranged from 30 to 60 nm, which was confirmed by TEM as well. The vibrating sample magnetometer (VSM) revealed a strong magnetization with paramagnetic behaviour, and the existence of all elements was verified by energy dispersive X-ray spectroscopy (EDS). According to the BET adsorption isotherm, total surface area ranges from 13.77 to 28.49 m2 g−1. At P/Po (0.99), the total pore volume ranges from 0.02 to 0.04 cm3 g−1. The average pore width ranged from 3.5 to 6.5 nm, and the isotherm demonstrates type III with an H3 hysteresis loop. The material shows 84% thermal stability and these synthesized nanoparticles are showing activity against both Gram-positive and Gram-negative bacterial pathogens. These synthesized nanoparticles are showing activity against both Gram-positive, Gram-negative bacteria and fungal pathogens, indicating broad-spectrum activity against microbial pathogens. The increased concentration of compound (0.1) showed antimicrobial activity against all the pathogens, which was measured as the zone of growth inhibition in diameter (mm) and compared with the standard antibiotics, streptomycin and clotrimazole. [ABSTRACT FROM AUTHOR]

The research and development of novel bistable magnetic materials is one of the most expanding areas of molecular magnetism. These materials are potentially suitable to be utilized in the construction of modern detectors, high-density data carriers, and devices for energy conversion. Until now, the greatest successes in this field have been achieved for magnetic cyanido-bridged metal assemblies. Among them, the greatest recognition is related to high-dimensional octacyanidometallate-based networks. In this Perspective, two- and three-dimensional cyanido-bridged CoII–[WV(CN)8] networks, exhibiting nontrivial magnetic properties (e.g., electron-transfer-coupled spin transition with broad thermal hysteresis and photoinduced spontaneous magnetization with relatively high Curie temperatures and large magnetic hysteresis loops) and other physicochemical properties (e.g., THz absorption and humidity sensitivity), are collected. All of them are model systems for development of bistable systems due to the presence of wide thermal hysteresis, and the formation of photoinduced metastable state tuned by temperature and wavelength of used light. Additionally, we summarized magnetostructural correlations within them, and we offered some guidelines for the improvement of their performances and the introduction of new functionalities and physicochemical cross-effects. [ABSTRACT FROM AUTHOR]