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We present micromagnetic simulations of spin–orbit torque (SOT)-induced multistate magnetization switching in a ferromagnetic layer with perpendicular anisotropy, conducted without an external magnetic field. Four volatile states are excited by a constant current. Each volatile state, after the removal of the current and undergoing relaxation and stabilization, can transition into one of four stable nonvolatile states. Further analysis revealed that, by specifically controlling the amplitude and active/inactive intervals of a rectangular pulse, a volatile state can transition to a robust nonvolatile state, providing a viable approach for multilevel magnetic data storage. The resistance of each magnetic domain state is qualitatively calculated, and their differences make these multilevel states detectable for information reading. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) magnetic materials offer promising prospects for applications in magnetic storage and spin field-effect transistors. However, the inherently low Curie temperatures of intrinsic 2D ferromagnetic semiconductor materials pose significant limitations on their practical device applications. An effective approach to achieving room-temperature ferromagnetism involves doping non-magnetic semiconductors with specific magnetic atoms. Here, we present the room-temperature ferromagnetism of chromium (Cr)-doped molybdenum disulfide (MoS2) nanosheets synthesized through chemical vapor deposition. The magnetic hysteresis loops, recorded across a temperature span of 10–300 K, underscore the remarkable stability of their magnetic attributes. To gain deeper microscopic insights into the magnetic properties of Cr-doped MoS2, we conducted first-principles calculations, which further validated our experimental findings. This research underscores a promising pathway for the development of 2D ferromagnetic materials with broad application potential in magnetic storage and spin field-effect transistors. [ABSTRACT FROM AUTHOR]

Magnetic vortices are being considered for information storage in magnetic devices. In this study, we used micromagnetic simulations to explore the effect of a perpendicular uniaxial anisotropy (PUA) on switching the vortex core in Permalloy nanodisks. We studied how the presence of the perpendicular uniaxial anisotropy (PUA) changes the spatial profile of the magnetic vortex. We determined the diameters of the vortex core as the perpendicular uniaxial anisotropy constant K z varied. Additionally, we determined the frequencies and spatial profiles of the radial modes of the spin waves. Our results show that the PUA affects the frequencies of the spin modes of a magnetic vortex in a nanodisk. We have also created phase diagrams demonstrating the areas where reversing the magnetic vortex core is possible by applying a sinusoidal field perpendicular to the nanodisk plane. [ABSTRACT FROM AUTHOR]

Comprehending the relationship between spin and phonons is essential to regulate the lattice thermal conductivity in 2D magnetic materials. Lattice thermal conductivity is a relevant part to consider in magnetic data storage and the working of spin-based devices. In this article, we examined the origin and effect of spin–phonon coupling (SPC) on the lattice thermal conductivity of pristine CrI 3 monolayer-based Janus monolayers Cr 2 X 3 S 3 (X = Br , I). We find a high SPC in these Janus monolayers due to in-plane Cr–S atomic vibrations. We observe a reduction in the lattice thermal conductivity at Janus monolayer magnetic states (∼ 52.3 % in Cr 2 Br 3 S 3 and ∼ 63.9% in Cr 2 I 3 S 3) compared to its paramagnetic states. The analysis is also conducted to determine which magnetic state has more anharmonicity using potential energy wells. A wide range of 2D magnetic materials can benefit from our results in the future development of spin-based thermal devices. [ABSTRACT FROM AUTHOR]

Encoding information in antiferromagnetic (AFM) domains is a promising solution for the ever growing demand in magnetic storage capacity. The absence of a macroscopic magnetization avoids crosstalk between different domain states, enabling ultrahigh density spintronics1 while being detrimental to the domain detection and manipulation. Disentangling these merits and disadvantages seemed so far unattainable. We report evidence for a new AFM domain selection mechanism based on non-Zeeman susceptibility anisotropy induced by the relative orientation of external magnetic fields to the k-domains. Consequently, the charge transport response is controlled by the rotation of the magnetic field and a pronounced anisotropic magnetoresistance is found in the AFM phase of bulk materials Nd1−xCex CoIn5. Our results and the domain switching theory2 indicate that this constitutes a new effect which might be universal across multiband materials. It provides a novel mechanism to control and detect AFM domains opening new perspectives for AFM sprintronics. [ABSTRACT FROM AUTHOR]

Increasing demand for advanced technologies that depends on magnetic phenomena, understanding and controlling the behavior of discrete breather in ferromagnetic nanowires are crucial for enhancing the efficiency and performance of such devices. The presence of octupole–dipole interactions signifies a unique aspect that could potentially influence the stability and localization of breather excitations. Hence, we adopted a multifaceted approach to investigate the Heisenberg anisotropic ferromagnetic nanowire discrete model with the following interactions: bilinear, octupole–dipole, anisotropy and its higher-order terms. The dynamics is governed by a discrete nonlinear Schrödinger equation (DNLS) arrived with the aid of Holstein–Primakoff transformation. This transformation was facilitated by utilizing the Glauber coherent representation of the boson operators. Subsequently, the dynamical equation is incorporated to the Modulational Instability (MI) analysis which is a systematical gateway to explore the breather excitation in the region of instability influenced by the octupole–dipole interaction coupling parameter. Then, we pictorially demonstrated that the octupole–dipole interaction plays a pivotal role in promoting the localization of discrete breather on the surface of the spin lattice sites in the discrete ferromagnetic nanowire. The energy density distribution also implies that the increase in octupole–dipole interaction results in the highly dense breather localization. The result shows that the increment in the octupole–dipole interaction parameter increases the amplitude of the localized breathers. These discrete breathers could hold immense promise for applications in magnetic storage and Spintronic devices, where maintaining stable localized modes is crucial for the device functionality. Our novelty lies in being pioneers in the exploration of a fully discrete model that encompasses higher-order interactions, such as the octupole–dipole interaction. We already have confirmed the existence of instability region on the discrete spin lattice by incorporating the octupole–dipole interaction [T. Pavithra, L. Kavitha, Prabhu and A. Mani, Modulational instability analysis in an isotropic ferromagnetic nanowire with higher order octopole-dipole interaction, in Nonlinear Dynamics and Applications: Proceedings of the ICNDA 2022 (Springer, 2022), p. 1209], we attempting to explore the generation of discrete breathers in a discrete anisotropic ferromagnetic nanowire. This effectively bridges the gap between theoretical understanding and practical implications, paving the way for innovative advancements in magnetic technology. [ABSTRACT FROM AUTHOR]

In this study, spinel NiFe2O4 nanoparticles were synthesized employing a one‐step flame spray pyrolysis technique and subjected to annealing at 500°C for 4 h. Thermal, structural, elemental, morphological, magnetic, and photoluminescence properties of the nanoparticles before and after annealing were evaluated using thermogravimetry–differential thermal analyzer, X‐ray diffraction (XRD), X‐ray photoelectron spectroscopy, scanning electron microscopy, dynamic light scattering, vibrating sample magnetometry, and fluorescence spectrometer, respectively. Results revealed a pronounced increase in particle size from an average of 80 nm to approximately 140 nm postannealing. XRD verified the retention of the cubic spinel structure with enhanced crystallinity and grain enlargement post‐thermal treatment, without the emergence of additional phases. The photoluminescence analysis showed distinct blue and green emission bands, with excitation at about 364 nm leading to blue emission at 500 nm and green emission at 550 nm both as‐prepared and postannealing. Additionally, magnetic characterization revealed an improvement in saturation magnetization from 16.31 emu/g for the as‐prepared samples to 29.68 emu/g postannealing, underscoring the annealing process's positive impact on magnetic properties. These findings emphasize the potential of tailored NiFe2O4 nanoparticles for applications in magnetic data storage, targeted drug delivery, and bioimaging, driven by modifications in their magnetic and photoluminescence characteristics through thermal treatment. [ABSTRACT FROM AUTHOR]

Magnetic tape provides a cost-effective way to retain the exponentially increasing volumes of data being created in recent years. The low cost per terabyte combined with tape's low energy consumption make it an appealing option for storing infrequently accessed data and has resulted in a resurgence in use of the technology. Magnetic tape as a digital data storage technology was first commercialized in the early 1950's and has evolved continuously since then. Despite its long history, tape has significant potential for continued capacity and data rate scaling. This article strives to provide an overview of linear magnetic tape technology, usage, history, and future outlook. After a short introduction, the article delves into the details of how modern tape drives and media operate, including the basic mechanism and physics of magnetic recording, current tape media technology, state-of-the-art tape head technology, tape layout and encoding, data retrieval, timing-based servo and mechatronics of a tape drive, and the capabilities of current drives. This is followed by a discussion of tape libraries, an overview of tape library performance modeling research, operating system-level and application-level tape support, tape use cases, and the future scaling potential and outlook of tape. The article concludes with a history of tape hardware, media, usage and software. [ABSTRACT FROM AUTHOR]

Since the discovery of ultrafast demagnetization in Ni thin films in 1996, laser-induced ultrafast spin dynamics have become a prominent research topic in the field of magnetism and spintronics. This development offers new possibilities for the advancement of spintronics and magnetic storage technology. The subject has drawn a substantial number of researchers, leading to a series of research endeavors. Various models have been proposed to elucidate the physical processes underlying laser-induced ultrafast spin dynamics in ferromagnetic materials. However, the potential origins of these processes across different material systems and the true contributions of these different origins remain challenging in the realm of ultrafast spin dynamics. This predicament also hinders the development of spintronic terahertz emitters. In this review, we initially introduce the different experimental methods used in laser-induced ultrafast spin dynamics. We then systematically explore the magnetization precession process and present seven models of ultrafast demagnetization in ferromagnetic materials. Subsequently, we discuss the physical processes and research status of four ultrafast demagnetization origins (including spin-flipping, spin transport, non-thermal electronic distribution, and laser-induced lattice strain). Since attosecond laser technique and antiferromagnetic materials exhibit promising applications in ultrahigh-frequency spintronics, we acknowledge the emerging studies used by attosecond pulses and studies on ultrafast spin dynamics in antiferromagnets, noting the significant challenges that need to be addressed in these burgeoning field. [ABSTRACT FROM AUTHOR]

The current study uses the Chernobyl disaster optimizer (CDO), a new metaheuristic optimizer, to identify the seven unknown parameters of solid oxide fuel cells (SOFCs). The procedures of the CDO is based on physical behavior of the elaborated radiations from the well-known Chernobyl disaster according to their mass, speed, frequency, and degree of ionization. The sum of square errors (SMSE) among the estimated and the real measured output voltage datasets of SOFCs is minimized employing the CDO. Set of boundaries of the SOFC's process is taken into consideration with the problem formulation. SOFCs stack's model is examined at 800οC and 900οC and its performance is confirmed. The CDO extracts more precise SOFCs' parameters compared to other competitors. The CDO's convergence patterns and the SOFCs unit's performance are studied and proved at steady-state by comparing its results to a number of recognized algorithms under varied operating scenarios. A significant SMSE's values of 3.46 µV2 and 7.38 µV2 are attained at 800οC and 900οC, respectively by the CDO. As a result, the polarization principal curves of the measured and estimated voltage datasets are checked and verified with very close matching. The dynamic behavior of the SOFCs stack is examined in relation to direct load, electric networks, and superconducting magnetic energy storage devices (SMES) for additional validation and illustration. The role of the SOFCs stack in controlling the active and reactive power delivered to the network and direct load is investigated using two controllers: one to control the inverter, which converts the SOFC's dc output to the main network, and the other to control the SMES. The Simulink/MATLAB environment is used to indicate the validity of the proposed framework under both steady-state and dynamical conditions. The comprehensive assessments show that the CDO capabilities are very effective when used with microgrids. [ABSTRACT FROM AUTHOR]

Magnetic heterojunctions with large exchange bias have promising applications in magnetic sensing and data storage. Ferromagnetic/antiferromagnetic (FM/AFM) heterojunctions are often used to generate exchange bias. However, the requirement of thermal manipulation makes controlling exchange bias in FM/AFM heterojunctions inconvenient. Herein, a Fe3GeTe2/Fe3GaTe2 FM/FM heterojunction is constructed to generate large exchange bias and reflected magnetic circular dichroism and magneto-optical Kerr effect techniques are used for the magnetic characterization of the heterojunction. The results show that strong magnetic coupling occurs at the Fe3GeTe2/Fe3GaTe2 interface when the temperature is <80 K. By fixing the spin direction of Fe3GaTe2, large exchange bias can be generated in Fe3GeTe2 because of the magnetic pinning effect. Furthermore, the strength of exchange bias can be manipulated by applying an ultralow current between Fe3GeTe2 and Fe3GaTe2 layers without changing the temperature. These results provide potential ways for generating and manipulating exchange bias in two-dimensional (2D) materials and pave the way for implementing the 2D van der Waals exchange bias effect in spintronic devices. [ABSTRACT FROM AUTHOR]

In this study, we investigated the stress-controlled magnetization processes and dynamic susceptibility of a magnetic vortex in FeGa disk under an external magnetic field. Our primary objectives were to elucidate the nucleation process of a magnetic vortex and explore the modulatory effects of mechanical stress on its behavior. Our findings reveal that the applied stress can regulate the spin arrangement, leading to different hysteresis loops with kinks of different switching processes in the magnetization. Specifically, tensile stress induces a buckling state, facilitating the transition from the parallel spin to the vortex state in smaller disks and introducing a distinct kink in the hysteresis loop. Conversely, compressive stress causes the disappearance of the original intermediate state in larger disks, leading to a smoother hysteresis loop. Notably, the stress-introduced magnetic anisotropy altered the resonance region of the system. These findings offer valuable insights into the design and optimization of magnetic storage devices and magnetic field sensors, highlighting the potential of harnessing mechanical stress as a tuning parameter for enhancing their performance. [ABSTRACT FROM AUTHOR]

Spintronic devices that utilize spin transfer torque are promising for integrated memory applications. However, these devices face substantial energy consumption challenges due to the high current densities required for switching. Conversely, voltage‐driven spintronic devices, using capacitive displacement charge, can realize switching operations that are energy‐efficient (≈1–10 fJ bit−1). This work investigates switching based on voltage control of the interlayer exchange coupling in perpendicular magnetic anisotropy (PMA) multilayered heterostructures. Unlike previous works that utilized gating techniques that employ ionic transport mechanisms to control interlayer exchange coupling, this study employs electrostatic gating by using MgO, which is more compatible with modern spintronic‐based memories. These results suggest that the magnetization anisotropy, and the magnitude, and phase of the Ruderman‐Kittel‐Kasuya‐Yosida (RKKY) coupling function with spacer layer thickness can be controlled through electric gating, providing a promising avenue for the development of energy‐efficient magnetic data storage devices. [ABSTRACT FROM AUTHOR]

Transition metal nitrides have extensive applications, including magnetic storage devices, hardware resistance coatings, and low-temperature fuel cells. This study investigated the structural, electrical, and mechanical properties of thin zirconium nitride (ZrN) films by examining the effects of laser irradiation times. Thin ZrN films were deposited on glass substrates using pulsed DC magnetron sputtering and irradiated with a diode laser for 6 and 10 min. Characterization was performed using X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), nanoindentation, and four-point probe techniques. Extended laser irradiation times resulted in increased numbers of peaks on XRD analysis, indicating enhanced crystalline behavior of thin ZrN film. SEM analysis revealed surface voids, while HRTEM showed nanostructured ZrN with uniform plane orientation. The electrical properties of the thin ZrN film improved with extended laser irradiation, as demonstrated by a reduction in sheet resistance from 0.43 × 109 Ω to 0.04 × 109 Ω. Additionally, nanoindentation tests revealed an increase in hardness, rising from 8.91 GPa to 9.36 GPa. [ABSTRACT FROM AUTHOR]

Zinc-incorporated manganese ferrite in polyvinylpyrrolidone matrices was successfully synthesized via a co-precipitation method at 1000 °C. Zn2+ doping was found to have a notable effect on the structural properties of the sample, as evidenced by XRD results indicating a cubic FCC structure with a ferrite spinel structure. The average crystallite size was 20.61 nm, and the lattice parameters of the samples varied slightly depending on the amount of Zn2+ doping. It was observed that Zn2+ doping increases both the magnetic moment and temperature of the sample. Zn2+ ions possess a large magnetic moment, which interacts with the other ions in the sample, resulting in an increased overall magnetic moment and coercivity. FE-SEM microstructure revealed cauliflower morphology, multiple pores, and rough aggregates. This increased magnetic moment was reflected in a specific capacitance value of 53.518Fg−1 at a scanning rate of 30mVs−1. Impedance analysis reveals that the relaxation phenomenon is highly dependent on concentration and frequency. PVP-coated Zinc-incorporated manganese ferrites are of great importance in technology and science due to their high saturation magnetization and low core losses. These ferrites have been widely utilized in electronic applications, such as magnetic storage devices, sensors, and microwave devices. [ABSTRACT FROM AUTHOR]

Owing to their high mobility and immunity to topological deflection, skyrmions in antiferromagnetic (AFM) systems are gaining attention as a potential solution for next‐generation magnetic data storage. Synthetic antiferromagnets (SAFs) offer a promising avenue to tune the properties of the individual magnetic layers, facilitating the conditions necessary for skyrmions to be used in practical devices. Despite recent advancements achieving fast skyrmion mobility, the nucleation of small and rigid circular skyrmions without an external field remains challenging in SAFs. Theoretical predictions suggest that optical vortex (OAM) beams can stabilize skyrmionic spin textures by transferring their spin and orbital angular momentum to the magnetic material. Here, this intriguing proposal is delved into and the creation of sub‐50 nm compact skyrmions in SAFs using OAM beams is successfully demonstrated, eliminating the need for external magnetic fields. Additionally, the results underscore the importance of beam energy and the number of pulses, as both factors play critical roles in the stabilization of these AFM skyrmionic textures. This breakthrough is significant as it paves the way for stabilizing true zero‐field skyrmions in AFM systems, where magnetization is minimally affected by external magnetic fields. This work will open a potential avenue for stabilizing small, compact skyrmions in antiferroic systems, facilitating their implementation in logic and memory devices. [ABSTRACT FROM AUTHOR]

La 0.7 Ca 0.3 MnO 3 (LCMO), with its high temperature coefficient of resistance (TCR) and large magnetoresistance (MR) effect, has emerged as a leading material in the field of new multi-functional ceramics. Enhancing the magnetoresistive effect of LCMO in low magnetic field and expanding its application range is one of the main research goals of this kind of materials. In this work, La 0.7- x Sm x Ca 0.3 MnO 3 (LSCMO) (0 ≤ x ≤ 0.09) ceramic targets with different doping amounts were successfully prepared by sol-gel method, and the influence mechanism of Sm3+ doping on the magnetoresistive effect and electrical transport performance of LSCMO was systematically analyzed. X-ray diffraction (XRD) results showed that the lattice parameters (a,b,c,V) of LSCMO decreased slightly, indicating that the doping amount of Sm3+ at the A-site increased. Scanning electron microscopy (SEM) showed that the grains were closely connected without obvious pores, the grain size decreased slightly. The ρ -T curve shows an obvious metal-insulator (M − I) transition, with the increase of Sm3+, the increase of resistivity, metal-insulator transition temperature (T MI) and ferromagnetic-paramagnetic (FM-PM) transition temperature (T C) move towards low temperature. When x = 0.015, the peak value of TCR reaches 41.94 %·K−1, and when x = 0.06, the peak value of MR reaches 80.25 %, both TCR and MR are improved. The results show that: Sm3+ doping can effectively enhance the electromagnetic transport performance of LSCMO. This material has a very wide application prospect in the fields of magnetic storage, and infrared detection. [ABSTRACT FROM AUTHOR]

This paper explores the impact of europium (Eu) and yttrium (Y) doping on the electronic, magnetic, optical, elastic, and structural properties of SmMnO3 perovskites using the Quantum ESPRESSO code. The cohesive energy and tolerance factor calculations revealed that the perovskite can maintain structural stability up to 25% doping of Eu and Y. Bandgap calculations suggest that when Eu and Y are doped, the energy bandgap of pure SmMnO3 decreases significantly from 2.72 to 0.47 and from 2.72 to 0.76 eV, respectively. Doped SmMnO3 exhibits a UV shift and increased intensity in the absorption coefficient, while the reflectivity peak decreases. These changes in optical properties and bandgap due to Eu and Y doping make SmMnO3 a promising material for advanced applications in photovoltaics, UV photodetectors, and optoelectronic devices. The ferromagnetic property and total magnetic moment of SmMnO3 are found to be increased by Eu doping. Meanwhile, the magnetic moment gets reduced by Y doping. Curie temperature calculations indicate that Eu doping increases the Curie temperature from 255.35 to 314.28 K, while Y doping reduces it from 255.35 to 187.69 K. These changes in magnetic moment and Curie temperature suggest that the doped material is suitable to be used in magnetic sensors and storage devices. The calculated elastic constants, Young's modulus, shear modulus, Poisson's ratio, and B/G ratio suggest that both pristine and doped compounds under study show a ductile behavior. [ABSTRACT FROM AUTHOR]

The editorial in the journal "Micromachines" focuses on the recent advances in micro/nano-fabrication, highlighting the importance of microscopic patterns and structures in various applications. The special issue covers sixteen papers that explore challenges and advancements in micro- and nanoscale fabrication processes, including methods like electrochemical machining and laser beam machining. The research presented in the issue offers valuable insights into the fabrication of complex material surfaces and provides a foundation for future developments in micro/nano-fabrication technology. [Extracted from the article]

High-entropy perovskite ceramics (HEPCs) with equal atomic ratios have recently emerged as a highly promising class of materials due to their unique magnetic properties. However, the crystal structure, microstructure and magnetic properties of unequal atomic ratios HEPCs have yet to be fully investigated. In this paper, single-phase HEPCs (La 0.25 Nd 0.25 Sm 0.25 Gd 0.25) 1- x Ho x MnO 3 ((LNSG) 1- x H x MO) have been synthesized using solid-state reactions. The effect of Ho element content (x = 0.25, 0.3, 0.35 and 0.4) on the structure and magnetic properties was systematically investigated. All samples exhibit an orthorhombic perovskite structure with a Pbnm space group and show obvious crystallization characteristics after sintering at 1250 °C for 16 h (LNSG) 1- x H x MO HEPCs display a smooth surface texture and distinct grain boundaries, as well as significant hysteresis effects at T = 5 K. The spin-orbit interaction and magnetic anisotropy between Ho and Mn ions increase with the increase of Ho content, which increases the saturation magnetization (M s) of HEPCs. (LNSG) 0.6 H 0.4 MO exhibits the lowest magnetic hysteresis losses among the considered samples, attributed to its highest M s (50.95 emu/g) and the lowest coercivity H c (0.6 kOe). These characteristics endow it with a potential application in magnetic storage devices. [ABSTRACT FROM AUTHOR]

Magnetic skyrmions and skyrmioniums have garnered significant attention due to their distinctive topologically nontrivial spin structures. Gaining a deep understanding of the magnetization dynamics of these structures and their interconversion processes is essential for fully leveraging their potential in magnetic storage technology. Here, the dynamics of strain-controlled generation and annihilation of skyrmions and skyrmioniums are investigated using phase field simulation methods. It is discovered that tensile strain can induce the transformation of a single domain into skyrmions and skyrmioniums, which can still exist stably after the strain is released. Notably, skyrmioniums demonstrate robust stability within a specific strain window of −0.2% to 0.5%. Beyond this, escalating the compressive strain magnitude induces a phase transition from skyrmioniums to skyrmions, culminating in a direct collapse to a single-domain state at a critical compressive strain of −0.8%. This study reveals that strain can effectively control a variety of topological magnetic domain structures and achieve their interconversion, providing guidance for the design of low-power, nonvolatile, multi-state spin storage devices. [ABSTRACT FROM AUTHOR]

Copper oxide (CuO) is an important transition metal oxide used in a wide variety of applications, such as gas sensors, magnetic storage media, lithium-ion electrodes, electronic device fabrication etc. CuO nanostructures (NS) exhibit exclusive properties considerably different from their bulk counterparts, such as highly reactive surfaces, different optical, electrical and catalytic properties which strongly depend on the shape, size and crystal structure of the NS. By altering the aspect ratio (length to diameter ratio) and shape of CuO NS, physical and chemical properties of these NS can be tailored. In this work, an array of CuO NS was synthesized on thin copper foil substrate through wet chemical route at different temperatures and times, followed by a thermal reduction in an Ar/H2 atmosphere. Cu foil itself was polished to different roughness levels and deformed to different thickness levels, prior to the reaction, to induce different growth conditions leading to the formation of CuO NS of different morphologies. The present study shows simple, scalable technique to synthesize various CuO NS that can be helpful in future to ameliorate various physical and chemical properties of CuO. [ABSTRACT FROM AUTHOR]

Holmium (Ho)‐doped bismuth ferrite (BiFeO3) nanoparticles are synthesized using the citrate‐gel autocombustion method to investigate their structural, dielectric, ferroelectric, and magnetic properties. X‐Ray diffraction analysis confirms the formation of a rhombohedral perovskite structure, with crystalline size decreasing from ≈14 to 7 nm as doping levels increase. Fourier‐transform infrared spectroscopy further validates the perovskite phase, while field emission scanning electron microscopy and energy‐dispersive X‐Ray spectroscopy confirm the nanocrystalline nature and composition of the samples. X‐Ray photoelectron spectroscopy verifies the successful incorporation of Ho3+ ions into the BiFeO3 matrix. The dielectric properties show high permittivity and low dielectric losses, while magnetic hysteresis loops reveal enhanced magnetic properties, including increased saturation magnetization, remanence, coercivity, squareness ratio, Bohr magneton, and magnetocrystalline anisotropy. These findings indicate that Ho‐doped BiFeO3 nanoparticles exhibit significantly improved electric and magnetic performance, positioning them as promising candidates for applications in magnetic storage devices and sensors. [ABSTRACT FROM AUTHOR]

Herein, the full potential linearized augmented plane wave (FP‐LAPW) method based on density functional theory has been used to compute the electro‐optical and magnetic characteristics of Mg1−xNixS (x = 0%, 6.25%, 12.5%, and 25%) alloys. The stability of the Mg1−xNixS alloys is verified by the enthalpy of formation energy. In electronic features, the band structure and density of states (DOS) demonstrate the semiconducting behavior in pristine MgS compound, while Mg1−xNixS alloys show half‐metallic ferromagnetic to metallic behavior based on the doping concentration. DOS exhibit a strong pd‐hybridization between Ni‐d and S‐p orbitals in the conduction band). For 6.25%, 12.5%, and 25% concentrations, the calculated total magnetic moment is 1.45364, 1.93086, and 0.71829 μB, respectively which is primarily owing to transition metal d states. Optical characteristics including refraction, absorption, complex dielectric function, and reflectivity are studied in the range of 0–10 eV at various concentrations. The absorption of light is noted from visible to UV spans which increase their significance for optoelectronic usages. Results of Mg1−xNixS alloys reveal their potential applications in optical and magnetic storage devices. [ABSTRACT FROM AUTHOR]

DFT studies are performed to investigate the crystal structure and geometry, electronic and magnetic properties of brownmillerite-type strontium-based oxygen-deficient perovskites SrTMO2.5 (TM = Mn, Fe, Co and Cu) in orthorhombic phase. The comparison of the calculated lattice parameters shows consistency with the experiments, and all these perovskites are thermodynamically stable as revealed by cohesive energy. The spin-dependent calculations of the electronic band profiles demonstrate the metallic behavior of all these deficient perovskites. The increase in electrical resistivity and electronic thermal conductivities with temperature also confirms the metallic behavior of these compounds. The optimized ground state energies in different magnetic phases and post-DFT treatment confirm that SrMnO2.5 and SrCoO2.5 are stable in C-type AFM, SrFeO2.5 is in G-type AFM and SrCuO2.5 in A-type AFM phase, respectively. The high specific heat of these deficient perovskites makes them good candidates for high-temperature technology. Based on the above physical properties, it is expected that these deficient perovskites are potential candidates for spintronics and magnetic storage devices. [ABSTRACT FROM AUTHOR]

Blade coating is a process that applies a fluid to a surface using a fixed blade. Among various coating technologies, blade coating offers significant economic advantages. It is commonly employed in the production of paper, information preservation, the application of coloring agents, and the manufacture of photographic films and magnetic storage devices. The novelty of this work lies in the investigation of the blade coating process for an electrically conducting Oldroyd 4‐constant liquid, incorporating velocity slippage at the blade surface in an area previously underexplored. The mathematical equations are modeled with the use of Lubrication Approximation Theory (LAT) and the normalized equations of the Oldroyd 4‐constant fluid are numerically solved by the Matlab built‐in function bvp4c using Regula‐Falsi Method. The impact of sundry parameters on physical quantities is examined through graphical representation. It is noted from the theoretical results that for the fixed value of the MHD parameter (M = 2.5), the coating thickness and blade load increased by 31% and 1648% respectively, for plane coater. For the exponential coater, these values increased by 29% and 1618% from their Newtonian value. These findings offer new insights into optimizing the blade coating process for complex fluid systems. [ABSTRACT FROM AUTHOR]

In the forefront of spintronic advancements, structures with strong perpendicular magnetic anisotropy (PMA) such as Pt/Co/Pt are essential for the miniaturization and performance enhancement of high-density magnetic storage technologies. The robust PMA characteristic of these systems facilitates the development of scalable spintronic devices, crucial for next-generation magnetic memory applications. This study investigates the interplay between PMA and the Dzyaloshinskii-Moriya interaction (DMI)—an antisymmetric exchange interaction prevalent in non-centrosymmetric magnetic systems—and its dissipative counterpart, chiral damping. While chiral damping arises from the same broken inversion symmetry as DMI, it typically introduces an additional energy dissipation channel, reducing device efficiency. Our research examines the effects of controlled helium ion (He+) irradiation on a Pt/Co/Pt system. We find that ion beam irradiation enhances interfacial intermixing, which correlates with a decrease in PMA. However, domain wall velocity measurements indicate a concurrent reduction in both DMI and chiral damping, along with enhanced velocities as irradiation fluence increases. These observations suggest that ion beam irradiation can be judiciously applied to achieve a balance between lower DMI, chiral damping, and reasonable PMA, thereby optimizing the system for improved device performance. [ABSTRACT FROM AUTHOR]

In this study, we investigate the thermal pinning and depinning behaviors of vortex domain walls (VDWs) in constricted magnetic nanowires, with a focus on potential applications in storage memory nanodevices. Using micromagnetic simulations and spin transfer torque, we examine the impacts of device temperature on VDW transformation into a transverse domain wall (TDW), mobility, and thermal strength pinning at the constricted area. We explore how thermal fluctuations influence the stability and mobility of domain walls within stepped nanowires. The thermal structural stability of VDWs and their pinning were investigated considering the effects of the stepped area depth (d) and its length (λ). Our findings indicate that the thermal stability of VDWs in magnetic stepped nanowires increases with decreasing the depth of the stepped area (d) and increasing nanowire thickness (th). For th ≥ 50 nm, the stability is maintained at temperatures ≥ 1200 K. In the stepped area, VDW thermal pinning strength increases with increasing d and decreasing λ. For values of d ≥ 100 nm, VDWs depin from the stepped area at temperatures ≥ 1000 K. Our results reveal that thermal effects significantly influence the pinning strength at constricted sites, impacting the overall performance and reliability of magnetic memory devices. These insights are crucial for optimizing the design and functionality of next-generation nanodevices. The stepped design offers numerous advantages, including simple fabrication using a single electron beam lithography exposure step on the resist. Additionally, adjusting λ and d allows for precise control over the pinning strength by modifying the dimensions of the stepped areas. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the effects of spin-transfer torques within the ferromagnetic infinite medium through the short-wave approximation method. As a result, we have derived the new (1 + 1) dimensional nonlinear evolution system, which describes the propagation of electromagnetic short waves within the ferromagnet in the presence of electric current density. Using the Painlevé analysis and Hirota's bilinearization, we unearth the integrability properties of this new evolution system. In the wake of such an analysis, the typical class of excitations and its physical implications are presented. We remark that the current density acts on magnetization like an effective magnetic damping, which is important for the stabilization of magnetic information storage and data process elements. [ABSTRACT FROM AUTHOR]

The sol-gel self-combustion technique was applied to form Cd–Co-based La-doped (Cd 0.5 Co 0.5 La x Fe 2-x O 4) spinel ferrite nanoparticles. A series of six samples was synthesized by varying lanthanum content from x = 0.00 to 0.20. The structural characteristics of the prepared nanoparticles were carried out using X-ray diffraction (XRD) analysis. The (311) plane verified that the prepared nanomaterials are in the spinel phase in all observed XRD patterns. The crystallite size for each sample was determined using the Scherrer formula found in the 8.7–17.8 nm range, which is well correlated with the SSP model. The crystallite size decreased while the lattice constant increased from 8.38 to 8.45 Å with increasing La-content. The increasing trend in the bulk density and X-ray density has been analyzed with the effects of La3+ contents. In Fourier-transform infrared spectroscopy (FTIR), the high-frequency absorption band (υ 1) was found from 522.15 to 541.06 cm−1, whereas the low-frequency band (υ 2) varied from 419.80 to 414.31 cm−1. The surface morphology was carried out by scanning electron microscope (SEM), which positively correlated with XRD analysis. Impedance analyzer (IA) assisted in observing the variations in complex dielectric properties of the compound in the frequency range from 1 MHz to 3 GHz. The dielectric constant and impedance plots depicted that the nano ferrites have good dielectric properties in low-frequency regions due contribution of polarization. While conduction can be made possible in the high-frequency areas as observed through AC conductivity. The electric modulus revealed the relaxation phenomenon at high frequency due to the hopping of electrons at the octa and tetrahedral sites. The magnetic properties were investigated to study the impact of La3+ ion under the applied magnetic field from −15 to 15 kOe. The saturation magnetization, and magnetic remanence were found from 40.6 to 27.7 emu/g and 19.6 to 2.7 emu/g, respectively. The synthesized nanoparticles can be utilized for microwave applications and magnetic storage devices. [ABSTRACT FROM AUTHOR]

The present study explored the impacts of dysprosium (Dy³⁺) doping on the structure, optical, and magnetic characteristics of CuDy x Fe 2-x O 4 nanospinel ferrites synthesized via a hydrothermal method. X-ray diffraction revealed a tetragonal spinel matrix with increasing Dy³⁺ content, accompanied by a secondary Dy 2 O 3 phase at higher dopant levels for x ≥ 0.1. Crystallite size and microstrain increased with doping, while infrared spectroscopy confirmed the spinel structure and distinct vibrational modes. Interestingly, saturation magnetization displayed a non-monotonic trend, first rising due to spin polarization and cation redistribution, then decreasing with higher Dy³⁺ content attributable to the Dy 2 O 3 phase and larger grains. Coercivity exhibited a maximum at x = 0.2, reflecting the interplay between magnetocrystalline anisotropy, canting angles, and domain wall pinning. These findings highlight the complex interplay between Dy³⁺ doping and the resulting properties, paving the way for tailored CuDy x Fe 2-x O 4 nanospinel ferrites functionalities.. Further research involving advanced techniques and targeted dopant levels holds promise for optimizing properties for diverse technological applications such as magnetic storage, microwave devices, sensors, and hyperthermia treatment. [ABSTRACT FROM AUTHOR]

Element-modified La 0.67 Ca 0.33 MnO 3 (LCMO) ceramics have been a major research subject in the past decades due to their various electromagnetic properties and potential applications in infrared detection and magnetic storage devices. However, its electromagnetic transport mechanism has not been fully elucidated and its properties need to be further optimized for practical applications. Here, we report the effect of Ni2+ doping on the structural, magnetic, the temperature coefficient of resistivity (TCR) and magnetoresistance (MR) properties of La 0.67 Ca 0.33 Mn 1- x Ni x O 3 (LCMNO) ceramics. All samples were synthesized by the sol-gel method and were in pure phase. XRD refinement results show a decrease in lattice constants and cell volume of LCMNO ceramics with increasing Ni2+ content. The XPS study confirms the reduction of the Mn3+/Mn4+ ratio and indicates that oxygen vacancies occur in LCMNO ceramics due to the Ni2+ doping. Curie-Weiss fitting results suggest ferromagnetic superexchange coupling between Ni2+ and Mn3+(4+) ions. The electrical transport properties of LCMNO ceramics were further investigated using the spin polaron hopping model in the high temperature range and the various competing scattering mechanisms in the low temperature range. In addition, double resistivity peak behavior is observed at x = 0.04 and 0.05. Furthermore, the TCR of the LCMNO ceramics increased to 45.4 %·K−1 (x = 0.01), while the MR increased to 67.9 % (x = 0.03), respectively. Our studies contribute to a better understanding of the electromagnetic properties of LCMNO ceramics. [ABSTRACT FROM AUTHOR]

The density functional theory (DFT) framework in the generalized gradient approximation (GGA) was employed to study the mechanical, dynamical, and thermodynamic properties of the ordered bimetallic Fe-Pt alloys with stoichiometric structures Fe3Pt, FePt, and FePt3. These alloys exhibit remarkable magnetic properties, high coercivity, excellent chemical stability, high magnetization, and corrosion resistance, making them potential candidates for application in high-density magnetic storage devices, magnetic recording media, and spintronic devices. The calculations of elastic constants showed that all the considered Fe-Pt alloys satisfy the Born necessary conditions for mechanical stability. Calculations on macroscopic elastic moduli showed that Fe-Pt alloys are ductile and characterized by greater resistance to deformation and volume change under external shearing forces. Furthermore, Fe-Pt alloys exhibit significant anisotropy due to variations in elastic constants and deviation of the universal anisotropy index value from zero. The equiatomic FePt showed dynamical stability, while the others showed softening of soft modes along high symmetry lines in the Brillouin zone. Moreover, from the phonon densities of states, we observed that Fe atomic vibrations are dominant at higher frequencies in Fe-rich compositions, while Pt vibrations are prevalent in Pt-rich. [ABSTRACT FROM AUTHOR]

The Janus MoSSe and alloy MoSxSe(1-x), belonging to the family of two-dimensional (2D) transition metal dichalcogenides (TMDs), have gained significant attention for their potential applications in nanotechnology. The unique asymmetric structure of Janus MoSSe provides intriguing possibilities for tailored applications. The alloy MoSxSe(1-x) offers a tunable composition, allowing for the fine-tuning of the properties to meet specific requirements. These materials exhibit remarkable mechanical, electrical, and optical properties, including a tunable band gap, high absorption coefficient, and photoconductivity. The vibrational and magnetic properties also make it a promising candidate for nanoscale sensing and magnetic storage applications. Properties of these materials can be precisely controlled through different approaches such as size-dependent properties, phase engineering, doping, alloying, defect and vacancy engineering, intercalation, morphology, and heterojunction or hybridisation. Various synthesis methods for 2D Janus MoSSe and alloy MoSxSe(1-x) are discussed, including hydro/solvothermal, chemical vapour transport, chemical vapour deposition, physical vapour depositio, and other approaches. The review also presents the latest advancements in Janus and alloy MoSSe-based applications, such as chemical and gas sensors, surface-enhanced Raman spectroscopy, field emission, and energy storage. Moreover, the review highlights the challenges and future directions in the research of these materials, including the need for improved synthesis methods, understanding of their stability, and exploration of new applications. Despite the early stages of research, both the MoSSe-based materials have shown significant potential in various fields, and this review provides valuable insights for researchers and engineers interested in exploring its potential. [ABSTRACT FROM AUTHOR]

The Sm0.47La0.20K0.33MnO3 perovskite manganite was synthesized using the solid-state reaction method and its structural, magnetic, and critical properties were investigated. This work analyzed the structural characteristics of our sample through Rietveld refinement of the X-ray diffraction pattern and Hirshfeld surface mapping (HS) techniques. It was shown that the sample crystallized in the space group Pnma, with the lattice parameters: a = 5.461 (4) Å, b = 5.478(1) Å, and c = 7.706(8) Å. The Mn–O bond length ~ 1.9 Å obtained from the Rietveld refinement, agrees with the minimum distances between Mn and O atoms obtained from the characteristic 2D fingerprint plots of this manganite. From M vs. T measurements in the range of 5 K < T < 300 K and isothermal measurements M (H) in the range of 0 T < H < 6.5 T , two phase transitions were observed: (i) a paramagnetic (PM)—ferromagnetic (FM) second-order phase transition, and (ii) a FM—spin-glass-like transition. The latter is associated with the presence of samarium in the crystalline structure of the manganite studied. Furthermore, a collective freezing state occurs at T B = 72.83 K . The behavior of the inverse of susceptibility χ - 1 (T) vs. T shows the coexistence of FM clusters within the PM state ( T > 184 K ). Modified Arrott plots (applied to 3D-Heisenberg, 3D-Ising, and Tricritical mean-field models), as well as the Kouvel-Fisher method, were employed to obtain the critical coefficients that were found to be β = 0.367 , γ = 1.330 , and δ = 4.776 for the Sm0.47La0.20K0.33MnO3 manganite. It was confirmed that both critical exponents (β and γ) satisfy the Widom scaling relation (δ = 1 + γ β) . However, a slight deviation from the theoretical values exists of the critical exponent δ obtained with the 3D Heisenberg model. This may be due to the nanoscale dimensions of the secondary phase KMn 2 O 6 particles. In conclusion, critical coefficients and observed phase transitions are significant because they provide guidance for theoretical modeling, enabling real-world applications in diverse technical domains, and shed light on material behavior, all of which contribute to our understanding of manganites. Based on the results of the search, it appears that a better understanding of the critical magnetic behavior in polycrystalline manganites may greatly improve future research and applications in the following areas: Hard disk drives HDDs and magnetic tapes are magnetic data storage devices which can benefit from manganite research to be advanced. Spintronics is a technology, which is based on electron spin polarization mechanism to process information. It utilizes manganites as an important material. [ABSTRACT FROM AUTHOR]

Topological magnetic states are promising information carriers for ultrahigh‐density and high‐efficiency magnetic storage. Recent advances in two‐dimensional (2D) magnets provide powerful platforms for stabilizing various nanometer‐size topological spin textures within a wide range of magnetic field and temperature. However, non‐centrosymmetric 2D magnets with broken inversion symmetry are scarce in nature, making direct observations of the chiral spin structure difficult, especially for antiferromagnetic (AFM) skyrmions. In this work, it is theoretically predicted that intrinsic AFM skyrmions can be easily triggered in XY‐type honeycomb magnet NiPS3 monolayer by alloying of Cr atoms, due to the presence of a sizable Dzyaloshinskii–Moriya interaction. More interestingly, the diameter of the AFM skyrmions in Ni3/4Cr1/4PS3 decreases from 12 to 4.4 nm as the external magnetic field increases and the skyrmion phases remain stable up to an external magnetic field of 4 T. These results highlight an effective strategy to generate and modulate the topological spin texture in 2D magnets by alloying with magnetic element. [ABSTRACT FROM AUTHOR]

Antiferromagnetic spintronics has been receiving attention recently, while spin-texture dependent magnetoresistance (MR) represents one of the main mechanisms for magnetic data storage. In particular, sufficiently large MR with high operating temperatures would be highly required for advanced spintronic applications. In this work, we experimentally investigate the MR effect of well-known antiferromagnet α-Fe2O3 (hematite) in a single crystal form, which has the Morin transition temperature as high as Tm ∼ 260 K. It is revealed that the MR effect associated with the spin-texture re-alignment, i.e., the spin-flop from the out-of-plane direction (c axis) to the in-plane direction, driven by sufficiently low magnetic fields inclined along the [012] direction, reaches up to ∼2.5% at temperature T ∼ 250 K. The first-principles calculations suggest that this MR effect originates from the reduced bandgap due to the spin-flop and the finite spin–orbital coupling. The present work sheds light on the possibility of α-Fe2O3 as a favored MR-based candidate for near-room temperature spintronics. [ABSTRACT FROM AUTHOR]

In this study, computational techniques based on artificial neural networks for three models were used for training sets, Néel's relaxation time, particle Length and the decay of magnetization were used to perform superparamagnetic calculations for Co3Pt and FePt typical magnetic storage medium. The magnetic medium's magnetisation stability was studied using the thermal stability coefficient by determining the Néel relaxation time. The superparamagnetic limit was discovered to determine the size of the magnetic particle that can maintain its magnetization for over 10 years, larger particles (8 nm3 for FePt and 64 nm3 for Co3Pt) are required. The decay of magnetization occurs when the thermal stability factor exceeds 40. the effect of changing the neural network's parameters on its performance was examined. The results demonstrated the high sensitivity of the designed neural network's response, which relies on the backpropagation technique to change these parameters. [ABSTRACT FROM AUTHOR]

The exceptional properties of two‐dimensional (2D) magnet materials present a novel approach to fabricate functional magnetic tunnel junctions (MTJ) by constructing full van der Waals (vdW) heterostructures with atomically sharp and clean interfaces. The exploration of vdW MTJ devices with high working temperature and adjustable functionalities holds great potential for advancing the application of 2D materials in magnetic sensing and data storage. Here, we report the observation of highly tunable room‐temperature tunneling magnetoresistance through electronic means in a full vdW Fe3GaTe2/WSe2/Fe3GaTe2 MTJ. The spin valve effect of the MTJ can be detected even with the current below 1 nA, both at low and room temperatures, yielding a tunneling magnetoresistance (TMR) of 340% at 2 K and 50% at 300 K, respectively. Importantly, the magnitude and sign of TMR can be modulated by a DC bias current, even at room temperature, a capability that was previously unrealized in full vdW MTJs. This tunable TMR arises from the contribution of energy‐dependent localized spin states in the metallic ferromagnet Fe3GaTe2 during tunnel transport when a finite electrical bias is applied. Our work offers a new perspective for designing and exploring room‐temperature tunable spintronic devices based on vdW magnet heterostructures. [ABSTRACT FROM AUTHOR]

We demonstrate direct printing from donor ink containing ferrite nanoparticles by employing laser induced forward transfer with an optical vortex possessing orbital angular momentum (OAM). We show, for the first time, that the as-printed dots are twisted and exhibit spinel Fe3O4 monocrystalline properties without the need for a sintering process. The helicity of the as-printed dots is shown to be selectively controlled merely by reversing the handedness of optical vortices. The diameter of the printed dots was typically measured to be less than 1/10th of the irradiated laser spot (diffraction limit). These results imply that the optical vortex twists and confines the sintered nanoparticles within its dark core to form chiral spinel monocrystalline dots. The observation of mono-crystallization with optical vortex induced forward transfer will offer new fundamental physics such as OAM light–matter interactions and could pave the way toward advanced printable magnetic devices, such as high-density magnetic data storage. [ABSTRACT FROM AUTHOR]

Co2Sn1−xTxO4 (T = Al, Sc, and Y; 0 ≤ x ≤ 0.2) magnetic spinel oxides have been synthesized through solid-state reaction. The XRD pattern displays a single-phase cubic structure with space group Fd3m. Moreover, magnetic susceptibility results show that substituting trivalent non-magnetic ions improves the para-ferrimagnetic transition temperature, TC. Magnetic susceptibility results of direct current (dc) and alternating current (ac) showed that the T3+ substitution increased the freezing temperature of the spin-glass state, and was also beneficial to the growth of the spin-glass phase. The apparent magnetic exchange bias effect at low temperatures (T < 20 K) was realized in the Co2Sn1−xTxO4 samples using the pinning effect in the spin-glass phase. Due to the magnetic exchange bias effect, the magnetism of the system dramatically increased at low temperatures. Thermal exchange bias results show that the coercivity field (HC) at 10 K increased from 0 for x = 0 samples to ~ 2.1, 1.3, and 2.9 kOe for Al-, Sc-, and Y-doped samples, respectively. It can optimize magnetic materials and architectures, improving performance and practicality in magnetic data storage, magnetic sensors, spintronics, and magnetic nanoparticles. [ABSTRACT FROM AUTHOR]

Due to the ever-increasing recording densities, disk-drive read channels are required to operate efficiently at high speeds. With the use of conventional design techniques, a compromise should be made between speed, power, latency and chip area. Improvements of head and media technology and the move from conventional single-track magnetic recording to two-dimensional magnetic recording help increase the areal density of magnetic data storage. Especially for the read channel, a performance gain is achieved by using more powerful coding and signal processing algorithms to mitigate inter-symbol and inter-track interferences. Timing recovery is essential to extract timing information in order to sample read data without a significant bit error, while calibration is performed to cancel the effects of gain and dc offset errors. Speed improvement and power consumption diminution are achieved in the resulting read channel system by using high-speed and power-efficient building blocks based on improved algorithms and pipeline stages to shorten critical paths. [ABSTRACT FROM AUTHOR]

Exploration and manipulation of topological protected magnetic swirls, such as skyrmion, antiskyrmion, meron, and vortex, holds significance for fundamental research and practical applications in high‐density magnetic information storage and spintronics because of their high storage density and low driven current. This study unveils the existence of field‐free spontaneous (anti)meron chains with a topological charge of ±1/2 in the centrosymmetric rare‐earth magnet Tb6Co2.17Si2.5 via in situ real‐space observation. The spin reorientation transition from in‐plane to uniaxial anisotropy contributes to the spontaneous transformation from straight domain walls to topological (anti)meron chains and to stripe domains along the [110] zone axis during in situ cooling. The study further confirms the critical role of the noncollinear magnetic structure of Tb atoms in the formation of topological (anti)meron chains via real‐space observations, first‐principles calculations, and micromagnetic simulations. The spontaneous topological magnetic texture is strongly correlated with the 4f electrons of rare‐earth atoms, enriching and stimulating alternative generation mechanisms of topological spin textures from emerging rare‐earth magnets, and further applications in spintronics. [ABSTRACT FROM AUTHOR]

We present an investigation into the magnetism exhibited by AMY2 compounds characterized by a chalcopyrite structure, where A can be Cu or Ag, M can be Sc, Ti, V, Cr, Mn, or Fe, and Y can be either S or Se. By substituting M atoms at the Ga position of AGaY2 compounds, the magnetic properties were calculated using the full potential linearized augmented plane wave method under the generalized gradient approximation and local spin density approximation with the WIEN2K code. The obtained spin-polarized results confirmed the presence of ferromagnetic and half-metallic (HM) properties in AMY2 compounds (A = Cu, Ag; M = Ti, V, Cr, Mn; Y = S, Se), wherein the HM property is preserved through p-d hybridization of p states of Y (S, Se) atoms with d (t2g) states of M (M = Ti, V, Cr, Mn) atoms, and minimal contribution of −s states of A (A = Cu, Ag) atoms. The total magnetic moments for AMY2 compounds were calculated as 1.00, 2.00, 3.00, and 4.00 µB/f.u. for M = Ti, V, Cr, Mn, respectively. For AFeY2 compounds (A = Cu, Ag; Y = S, Se), electronic band structures for both up spin and down spin states were identical, suggesting antiferromagnetic behavior at equilibrium, while AScY2 compounds (A = Cu, Ag; Y = S, Se) exhibited nonmagnetic properties at equilibrium. Overall, the accurate HM properties of AMY2 materials suggest promising prospects for their utilization in spintronics and magnetic storage device applications. [ABSTRACT FROM AUTHOR]

The Present work represents the Structural, morphological, magnetic, and optical properties of Pristine and Ni-doped La 2 SrFe 2 TiO 9 Triple Perovskite. The samples were synthesized by using the solid-state reaction approach. We have carried out the structural characterization of the La 2 SrFe 2-x Ni x TiO 9 (x = 0.0, 0.1, 0.2, 0.3 and 0.5) Triple Perovskite by using X-ray diffraction and found that all the synthesized samples were grown in a single phase with space group (Pnma) which has been confirmed further by Rietveld Refinement. The microstructural analysis and the elemental composition analysis were carried out using a Field Emission Scanning Electron Microscope (FE-SEM) and Energy dispersive spectroscopy (EDS) respectively. The morphological studies of the sample reveal that the grain size of the sample decreases (1.11–0.75 μm) with Ni Doping. The optical band gap of the samples was characterized by UV–vis spectroscopy measurements, and we have obtained the value of the energy band gap from 2.02 to 1.67 eV, confirming the application of the material in the Infrared region of the electromagnetic spectrum. The M − H measurements reveal the stabilized ferromagnetic character of the pure La 2 SrFe 2 TiO 9 Triple Perovskite upon Ni doping. The XPS Studies confirm that Ni exists in the form of Ni2+ while Fe exists in the form of Fe3+. The magnetic measurements were understood theoretically by using the mathematical equation. The current study indicates the stability of the samples, and their possible utilisation in spintronics, magnetic storage devices, magneto-optoelectronics, and solar cell applications. [ABSTRACT FROM AUTHOR]

Strontium-zirconium ferrite (Sr–ZrFe) nanocomposites are prepared by the co-precipitation method. Zirconium is taken in two ratios (20% & 50%) with strontium of (80% & 50%) in the synthesis process to make Sr 0.8 Zr 0.2 Fe 12 O 19 and Sr 0.5 Zr 0.5 Fe 12 O 19 which are mentioned as Sr–ZrFe1 and Sr–ZrFe2. The nanocomposites' crystallite size is ascertained by applying the Scherrer equation is 20.97 nm and 21.09 nm. The SEM micrographs show the hexagonal shape of the synthesized nanocomposites. The EDS spectrum depicts the nanocomposites' atomic percentage. The coercivity of the nanocomposites calculated is (H c) = 0.4353 Oe and 0.4450 Oe. From the magnetic hysteresis loop, both composites are found to be single-domain soft ferromagnetic materials. Therefore, the synthesized composites can be used as magnetic data storage devices. The Kubelka-Munk plot is used for obtaining the band gap energy from the UV-DRS reflectance data. The highest intensity peaks of Sr–ZrFe1 and Sr–ZrFe2 nanocomposites are studied from the PL analysis. [ABSTRACT FROM AUTHOR]