Magnetic Properties Research Articles

Effect of Cu Additive on the Microstructure and Magnetic Properties of Fe-6.5wt%Si High Silicon Steel by Induction Melting Method

Fe-6.5wt%Si high silicon steel alloy was prepared using the vacuum induction melting method. Ordered phase formation in Fe-6.5wt%Si alloy was inhibited by adding trace Cu and induction cycle heating purification treatment. The microstructure and magnetic properties of high silicon steel were investigated. The results show that with the increase of Cu content, the alloy microstructure first changed from coarse grain to fine isoaxial crystal, followed by strip dendrite, with ordered cracking. The saturated polarization strength of the alloy decreased from 25.1 emu of the sample without adding Cu and heating once to 21.5 emu for seven cycles, the residual magnetic polarization increased from 0.0255 emu to 0.048 emu, the slope of the magnetization curve slowed down, and the coercive force increased from 2.4 Oe to 4.0 Oe. With the increase of cyclic heating times, the microstructure of the alloy without added Cu refined and transitioned from columnar to equiaxial crystals, from isoaxial dendrite to strip with the addition of 0.03 wt%Cu, and from strip to isoaxial structure with the addition of 0.05 wt%Cu. With the increase of cycle heating times, the saturation magnetization strength of the alloy without Cu and with 0.03 wt%Cu alloy increased, while the recalcitrant force reduced. Conversely, the saturation polarization strength decreased for the alloy with 0.05 wt% Cu, and the coercive force was also reduced.

Efficient and Stable Red‐Orange Emission from Polaronic Magnetic Excitons in Mn (II)‐Doped 0D All‐Inorganic Rb4CdCl6

AbstractThe impact of magnetic coupling effects on the luminescence of 0D (zero‐dimensional) perovskite materials doped with TM (transition metal) ions remains underexplored. This study synthesizes Mn2+‐doped 0D Rb4CdCl6 halide structures using a solvent‐based method, with Rb+ ions systematically arranged around isolated [CdCl6]4− octahedra. The resulting Rb4Cd1‐xMnxCl6 powder exhibits stable orange‐red luminescence under UV (ultraviolet) excitation, achieving a PLQY (photoluminescence quantum yield) of 88.96%. The parent Rb4CdCl6 is non‐luminescent, but doping with Mn2+ induces strong luminescence due to combined emissions from d‐d transitions of Mn2+, weakly ferromagnetically coupled Mn2+ pairs, and STEs (self‐trapped excitons). Characterization via XRD (X‐ray diffraction) and DFT (density functional theory) reveals that Mn2+ doping occurs through both substitutional and interstitial processes, facilitating magnetic coupling. Raman spectroscopy identifies strong electron‐phonon coupling at a phonon mode of 112 cm−1, supporting STEs generation. Magnetic property analysis shows significant ferromagnetic coupling between Mn2+ pairs and paramagnetic single Mn2+ ions, enhancing luminescence. The material demonstrates remarkable structural and thermal stability, positioning Rb4Cd1‐xMnxCl6 as a promising candidate for optoelectronic applications.

Spectral and magnetic properties of the jet base in NGC 315

The dynamics of relativistic jets in inner parsec regions are deeply affected by the nature of magnetic fields. The level of magnetization of the plasma as well as the geometry of these fields on compact scales have not yet been fully constrained. In this paper, we employ multi-frequency and multi-epoch very long baseline interferometry observations of the nearby radio galaxy NGC 315. We aim to derive insights into the magnetic field properties on sub-parsec and parsec scales by examining observational signatures such as the spectral index, synchrotron turnover frequency, and brightness temperature profiles. This analysis was performed by considering the properties of the jet acceleration and collimation zone, which can be probed thanks to the source vicinity as well as the inner part of the jet conical region. We observed remarkably steep values for the spectral index on sub-parsec scales ($ -2$, $S_ which flatten around $ -0.8$ on parsec scales. We suggest that the observed steep values may result from particles being accelerated via diffusive shock acceleration mechanisms in magnetized plasma and subsequently experiencing cooling through synchrotron losses. The brightness temperature of the 43\,GHz cores indicates a dominance of the magnetic energy at the jet base, while the cores at progressively lower frequencies reveal a gradual transition toward equipartition. Based on the spectral index and brightness temperature along the incoming jet and by employing theoretical models, we derived that the magnetic field strength has a close-to-linear dependence with distance going from parsec scales up to the jet apex. Overall, our findings are consistent with a toroidal-dominated magnetic field on all the analyzed scales.

Magnetic Properties of All-d Metallic Heusler Compounds: A First-Principles Study

All-d metallic Heusler compounds are promising materials for nanoelectronic applications. Such materials combining 3d, 4d, and 5d atoms have not yet been studied. In this respect, we perform ab initio electronic structure calculations and focus on Co2MnZ, Rh2MnZ, and Ru2MnZ compounds, where Z represents transition metal atoms from groups 3B, 4B, 5B, and 6B of the periodic table. Our results demonstrate that most of these compounds exhibit a distinctive region of very low minority-spin state density at the Fermi level when crystallized in the L21 lattice structure. The Co-based compounds follow a Slater–Pauling behavior for their total spin magnetic moments, while the Ru-based compounds consistently deviate from the predicted Slater–Pauling values. Rh-based compounds show similarities to Co-based compounds for lighter Z atoms and to Ru-based compounds for heavier Z atoms. We find that the choice of the Z element within the same periodic table column has only a minor effect on the results, except for the Rh2Mn(Cr, Mo, W) compounds. Our findings suggest that these compounds hold significant promise for applications in spintronics and magnetoelectronics.

Electronic, magnetic, and topological properties of ferromagnetic 2D perovskite-type oxides

Abstract Two-dimensional (2D) materials within the hematene-type binary oxides and perovskites family have recently gathered huge research interest for nanoelectronic devices. However, the exploration of their fascinating topological properties remains limited. Herein, through first-principles calculations, we systematically examine the electronic, magnetic, and topological properties of substitutionally doped 2D ABO3 (A=As, Sb, or Bi, and B = V, Nb, or Ta) perovskite structures at the B site of a B2O3 system. Interestingly, the atomic substitution makes the 2D ABO3 structures dynamically stable. Our detailed calculations show the ferromagnetic and antiferromagnetic phases of these materials. The calculated Chern number (C) for the ferromagnetic 2D ABO3 (A = As, Sb, or Bi, B = Nb or Ta) suggests their topologically non-trivial phases. Furthermore, the computed nontrivial Berry curvature highlights the topological properties in AsNbO3. These findings highlight opportunities in 2D-ABO3 materials, for applications in spintronics.

Shot Noise in a Metal Close to the Mott Transition.

SrIrO3 is a metallic complex oxide with unusual electronic and magnetic properties believed to originate from electron correlations due to its proximity to the Mott metal-insulator transition. However, the nature of its electronic state and the mechanism of metallic conduction remain poorly understood. We demonstrate that the shot noise produced by nanoscale SrIrO3 junctions is strongly suppressed, inconsistent with diffusive quasiparticle transport. Analysis of thermal effects and scaling with the junction length reveals that conduction is mediated by collective hopping of electrons almost localized by correlations. Our results provide insight into the non-Fermi liquid state close to the Mott transition and advance shot noise measurements as a powerful technique for the study of quantum materials.

Spectroscopic analysis of 2-mercaptobenzothiazole charge-transfer compounds with chloranilic acid and chloranil: morphological characterization, magnetic properties, and DFT investigations

Spectroscopic analysis of 2-mercaptobenzothiazole charge-transfer compounds with chloranilic acid and chloranil: morphological characterization, magnetic properties, and DFT investigations

Обзор исследований высокоэнтропийных сплавов, их свойств, методов создания и применения

Introduction. The paper discusses the prospects for studying high-entropy alloys (HEA), metal materials with unique properties. The study of high-entropy alloys is an urgent area of research in connection with its properties, environmental sustainability, economic benefits and technological potential. HEA are of interest to researchers due to its stability, strength, corrosion resistance and other characteristics, which makes it promising for use in the aerospace industry, automotive, medicine and microelectronics. Thus, HEA research contributes to the development of new materials and technological progress, providing opportunities for creating innovative products and improving existing solutions. To effectively use the potential of high-entropy alloys, research is required in a number of areas. First, it is necessary to improve the production technology of such alloys and develop new methods for obtaining HEA with improved characteristics and reduced cost. Secondly, it is necessary to establish the basic principles of operation of high-entropy alloys and to study the mechanisms influencing its properties. It is also necessary to develop new alloys with specified properties and conduct experiments and computer simulations to optimize the characteristics of the alloys and determine the best compositions. The purpose of the work is to study developments in the field of high-entropy alloys and conduct a comparative analysis of published studies on improving the properties of high-entropy alloys. The research method is a review and analysis based on developments mainly for 2020-2024, which were carried out by domestic and foreign scientists. The paper discusses the prospects for the study of high-entropy alloys, materials with a wide range of applications in various industries. The paper presents the results of research, mainly for 2020-2024. The main properties of high-entropy alloys are described, such as high strength, corrosion resistance, fatigue properties, plasticity and deformability, thermal stability, electrical conductivity and magnetic properties, as well as the possibility of creating alloys with specified characteristics. The most common methods of changing the properties of alloys have been identified. The directions of further development of research in this area are considered. Results and discussion: a literature review shows that developments and research are carried out on all possible properties of HEA, but most of it is devoted to corrosion-resisting properties and thermal stability. Of the methods used in high-entropy alloys, the most common and universal can be considered the alloying of high-entropy alloys with other metals. Studies also confirm that alloying metals are selected depending on its characteristic properties. The number of scientific works also confirms the relevance of this topic and the need for its study. The authors noted that future studies on the fatigue properties of high-entropy alloys, as well as the properties of alloys under the influence of magnetic and electric fields are the most interesting.

Correction to: Tuning the Structure, Magnetic, and High Frequency Properties of Sc‐Doped Sr0.5Ba0.5ScxFe12‐xO19/NiFe2O4 Hard/Soft Nanocomposites

Correction to: Tuning the Structure, Magnetic, and High Frequency Properties of Sc‐Doped Sr0.5Ba0.5ScxFe12‐xO19/NiFe2O4 Hard/Soft Nanocomposites

Ferromagnetic Exchange and Slow Magnetic Relaxation in Cobalt Bis(1,2-dithiolene)-Bridged Dilanthanide Complexes.

The construction of multinuclear lanthanide-based molecules with significant magnetic exchange interactions represents a key challenge in the realization of single-molecule magnets with high operating temperatures. Here, we report the synthesis and magnetic characterization of two series of heterobimetallic compounds, (Cp*2Ln)2(μ-Co(pdt)2) (Ln = Y3+, Gd3+, Dy3+; pdt2- = 1,2-diphenylethylenedithiolate) and [K(18-crown-6)][(Cp*2Ln)2(μ-Co(pdt)2)] (Ln = Y3+, Gd3+), featuring two lanthanide centers bridged by a cobalt bis(1,2-dithiolene) complex. Dc magnetic susceptibility data collected for the Gd congeners indicate significant Gd-Co ferromagnetic exchange interactions with fits affording J = +11.5 and +7.33 cm-1, respectively. Magnetization decay and ac magnetic susceptibility measurements carried out on the single-molecule magnet (Cp*2Dy)2(μ-Co(pdt)2) reveal full suppression of quantum tunneling and open-loop hysteresis persisting up to 3.5 K. These results, along with those of high-field EPR spectroscopy, suggest that transition metalloligands can enforce strong exchange interactions with adjacent lanthanide centers while maintaining a geometry that preserves molecular anisotropy. Furthermore, the magnetic properties of [K(18-crown-6)][(Cp*2Gd)2(μ-Co(pdt)2)] show that increasing the spin of the ground state of the bridging complex may be a viable alternative to increasing J in obtaining well-isolated, strongly coupled magnetic ground states.

Effect of Mn Doping on the Modulation of Magnetoelectric and Mechanical Properties of Cu–Ni–Sn Alloys

In this research, the magnetoelectric and mechanical properties of Cu77–xNi15Sn8Mnx (x = 0, 5, 10, 15, 20 at%) alloy are systematically studied. In the results, it is demonstrated that the magnetic properties of the alloy increase with an increase in the Mn content, as evidenced by the thermomagnetic curve and isothermal magnetization curve. The magnetic properties of the annealed Cu57Ni15Sn8Mn20 alloy reach about 15 emu g−1 at room temperature, and the Curie temperature (Tc) reaches about 360 K in a 1 k Oe magnetic field. The characteristic peak of the magnetic transition in the AC magnetic susceptibility test also corresponds to the Curie temperature. An electrical performance test calculated the resistivity of the alloy, the resistivity of Cu57Ni15Sn8Mn20 in its annealed state is about 26% lower than that of Cu77Ni15Sn8. Furthermore, the hardness test reveals that the Vickers hardness of the Cu57Ni15Sn8Mn20 alloy is about 246.2 HV, demonstrating its excellent mechanical properties. In the research, it is shown that the doping of Mn elements plays a crucial role in the magnetic properties of Cu–Ni–Sn alloys. By adjusting the content of the Mn element, the magnetic performance can be controlled. A valuable approach is provided for enhancing the performance of magnetic Cu alloys.

Phase stability and magnetic properties of RE2Fe14C system with B substitution: a theoretical investigation

Phase stability and magnetic properties of RE2Fe14C system with B substitution: a theoretical investigation

Spin glass behavior of single-crystalline ErFe2O4−δ

Abstract We investigated magnetic properties of ErFe2O4-δ single crystal containing oxygen vacancies with value of δ being estimated to be 0.066. The temperature dependence of dc magnetization in zero field cooling (ZFC) process reveals that ErFe2O4-δ undergoes a ferrimagnetic transition at 234 K followed by a broad peak at 224.3 K. The latter is attributable to the spin glass transition as indicated by the strong frequency dependence of temperature-dependent ac susceptibility. The frequency variation of transition temperature is described well by the dynamic scaling law and the critical exponent is similar to those reported for typical spin glasses. Additionally, the spin glass transition at 224.3 K is confirmed by the fact that the magnetic field dependence of irreversible transition temperature is coincident with the de Almeida-Thouless line and that the aging memory and rejuvenation effect is observed. Noticeably, ErFe2O4-δ single crystal exhibits the field-cooled hysteresis loop shift and training effect below 200 K, suggesting the occurrence of exchange bias effect originating from the spin glass phase.

Annealing Temperature Effect on the Properties of CoCe Thin Films Prepared by Magnetron Sputtering at Si(100) and Glass Substrates

This study explores cobalt–cerium (Co90Ce10) thin films deposited on silicon (Si) (100) and glass substrates via direct current (DC) magnetron sputtering, with thicknesses from 10 nanometer (nm) to 50 nm. Post-deposition annealing treatments, conducted from 100 °C to 300 °C, resulted in significant changes in surface roughness, surface energy, and magnetic domain size, demonstrating the potential to tune magnetic properties via thermal processing. The films exhibited hydrophilic behavior, with thinner films showing a stronger substrate effect, crucial for surface engineering in device fabrication. Increased film thickness reduced transmittance due to photon signal inhibition and light scattering, important for optimizing optical devices. Furthermore, the reduction in sheet resistance and resistivity with increasing thickness and heat treatment highlights the significance of these parameters in optimizing the electrical properties for practical applications.

Single-Molecule Magnet Behavior and Spin Structure of an FeIII7 Cartwheel Cluster Revealed by Sub-Kelvin Magnetometry and Mössbauer Spectroscopy: The Final Pieces of the Puzzle.

The spin frustration and other magnetic properties of the "cartwheel" heptanuclear cluster [FeIII7O3(O2CtBu)9(Me-dea)3(H2O)3] (Me-deaH2 = N-methyldiethanolamine) have been previously investigated; we present here a Mössbauer spectroscopic study and sub-Kelvin magnetization and ac susceptibility measurements which enable a complete magnetic picture of this frustrated cluster. 57Fe Mössbauer spectra above 150 K showed three doublets in a 1:3:3 ratio, which could be assigned by their respective quadrupole splittings to the central Fe(1) and the peripheral Fe(2) and Fe(3). The field dependence of the corresponding magnetic sextets at 3 K showed that the spins on the central Fe(1) and the three peripheral Fe(2) sites with O5N coordination are oriented mutually coparallel, while these are antiparallel to the spins on the peripheral Fe(3) sites with O6 coordination, resulting in an overall S = 5/2 ground state. This provides experimental confirmation of the previously proposed spin ground state structure. Upon cooling to sub-Kelvin temperatures, a crossover to spin blocking with TB ≈ 0.21 K could be observed. This single-molecule magnet behavior had been expected but had not been observable with a conventional SQUID. The anisotropy barrier, of 3-fold symmetry, can be described in terms of the parameter D/kB = -0.47 K and a fourth-order perturbation; the latter enables thermally activated quantum tunneling through the excited sublevel mz = ± 3/2, with an activation barrier of U/kB = 1.9 K.

Structural, Optical, Magnetic and Electrical Properties of Zinc Oxide Doped with Iron: A Review

This study reviewed the structural, optical, magnetic and electrical properties of zinc oxide (ZnO) nano-particles doped with iron relative to zinc oxide. ZnO is an excellent nanomaterial in semiconductor industries because of its properties such as low cost, high stability and high absorbance. However, its application has been limited because of some undesirable characteristics. Hence, doping with iron has proven essential in overcoming these limitations. The X-ray diffraction studies show that the structure is hexagonal with wurtzite structure, ZnO films prefer to grow in the (002) direction. This is because each apex is parallel to the c-axis in the wurtzite structure. This review reported that optical band gap ZnO nano-particles doped with iron was found to be in the range to (3.26 - 3.35) eV. The electrical properties of these films indicated low resistivity and consequently high electrical conductivity at high dopant iron concentration. Consequently, higher electrical resistivity was observed with lower conductivity at lower iron dopant concentration. Higher iron-doped ZnO (x=0.10 and 0.20) samples exhibited obvious ferromagnetic behaviors suggesting that saturation magnetization of Zn1-xFexO nano-particles increases with the increasing of Fe doping concentration compared with pure ZnO. Hence the SEM of iron-doped zinc oxide nano-particles consists of ellipsoidal shape particles, which are well dispersed with smooth surface and uniform size.

A Comprehensive Review of MXene-Based Emerging Materials for Energy Storage Applications and Future perspectives.

MXenes is a rapidly emerging class of two-dimensional (2D) materials. It exhibits unique properties that make it suitable for a wide range of applications. This review provides a comprehensive overview of the synthesis and processing techniques for MXenes including both bottom-up and top-down approaches. The synthesis of MXene-based composites is explored in detail focusing on MXene-carbon composites, MXene-metal oxides, MXene-metal sulfides, MXene-polymer composites and MXene-ceramic composites. Key properties of MXenes are examined including structural, electrical, morphological, optical, mechanical, chemical stability, electrical and thermal properties, conductivity, magnetic properties, dielectric charge and catalytic properties. Characterization techniques used to study these properties are also reviewed. Their 2D structure provides a high surface area and unique interlayer spacing, making MXenes ideal for applications in energy storage devices (like supercapacitors and batteries) where surface area and ion transport are critical for performance. The diverse applications of MXenes are presented emphasizing their use in batteries, catalysis, sensors, environmental remediation and supercapacitors. Special attention is given to the supercapacitor applications of MXenes of their potential in energy storage devices. Due to their high capacitance, fast charge/discharge rates, and excellent stability, MXenes are used in supercapacitors, lithium-ion batteries, and sodium-ion batteries.

Fluoride Clusterfullerenes: Tuning Metal-Metal Bonding and Magnetic Properties via Single Fluorine Atom Doping.

Endohedral fullerenes are known for their exceptional ability to host metal clusters that contain unique bonding motifs. In this study, we report a facile strategy to synthesize a new family of clusterfullerenes, fluoride clusterfullerenes (FCFs). This work demonstrates that actinides and rare earth metals as well as alkaline earth metals can be encapsulated within a variety of fullerene cages, and these fullerenes can be obtained in their pristine form without additional functionalization methods. Notably, Th2F@Ih(7)-C80 and CaScF@Cs(6)-C82 were isolated and their molecular structures and magnetic properties were characterized by X-ray single-crystal diffraction and multiple spectroscopic techniques as well as DFT calculations. These findings reveal that the unique internal addition of a single fluorine atom significantly alters the metal-metal bonding interactions of Th-Th and Ca-Sc. While Th2@Ih(7)-C80 hosts a σ2 Th-Th bond, an unprecedented actinide-actinide (Th-Th) single electron metal-metal bond is formed inside Th2F@Ih(7)-C80 upon the internal addition of fluoride. Similarly, while a Ca-Sc single electron bond exists in CaSc@Cs(6)-C82, which exhibits excellent molecular qubit properties, the addition of fluoride transforms the compound into a singlet. The present study not only highlights the successful synthesis of a novel family of FCFs, which will likely be an extensive family, it also shows that fluorine doping can induce novel metal-metal bonding motifs leading to potentially intriguing magnetic properties.

Correction: Investigation of the structural, electronic, magnetic, mechanical, and optical properties of calcium-based CaJO3 (J = Mn, Ru) perovskites: A first-principle computations

Correction: Investigation of the structural, electronic, magnetic, mechanical, and optical properties of calcium-based CaJO3 (J = Mn, Ru) perovskites: A first-principle computations

Computational characterization of structural, electronic, elastic and magnetic properties of double half-Heusler alloy Fe2MnCoGe2

Using the augmented plane wave method based on density functional theory and implemented in the WIEN2k code, we study the structural, elastic, electronic, and magnetic properties of FeCoGe, FeMnGe, and the parent half-Heusler (HH) alloys, as well as their derivative Fe2CoMnGe2 double half-Heusler (DHH) compounds. By analysing the stability of the HH structure in both the ferromagnetic and non-magnetic phases of FeCoGe and FeMnGe alloys, we determine that the latter phase of type II and type III FeCoGe and FeMnGe arrangements is the most stable. The Fe2CoMnGe2 DHH alloy, which is derived from the magnetic and structural ground states of FeCoGe and FeMnGe HH alloys, is found to be most stable in the type II arrangement. Among these materials, the FeMnGe HH alloy demonstrates greater resistance to reversible deformation by shear strain, indicated by its higher Young's modulus, while FeCoGe shows the best overall resistance to deformation. The electronic structures of FeCoGe, FeMnGe, and Fe2CoMnGe2 compounds reveal metallic behavior in the spin-up channel and semiconducting behavior in the spin-down channel. Their half-metallic gaps are 0.437 (0.181) eV, 0.543 (0.224) eV, and 0.353 (0.035) eV, respectively, with Fe2CoMnGe2 DHH retaining half-metallicity despite a lower band gap. The total magnetic moments for FeCoGe, FeMnGe, and Fe2CoMnGe2 are found to be 3, 1, and 4 μB, respectively. Given their half-metallic properties, these alloys show potential as candidates for spintronic applications.