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Our current study employs the spin-polarized density functional theory (DFT) using the all-electron full potential linear augmented plane-wave method (FP-LAPW) to examine the structural, electronic, and magnetic properties of InSb doped with Tungsten (In WxSb with x = 0.125, 0.25) in the zinc blende crystal structure. We used, for the electronic exchange and correlation energy, the generalized gradient approximation (GGA) with the Wu-Cohen (WC) functional, improved with the Tran–Blaha modified Becke–Johnson (TB-mBJ) approach for the electronic properties. The obtained results show that this calculation method allows for reliable band gap values. The estimated structural properties match well with existing experimental results. The value of the total magnetic moment is around 3.00 µB for the investigated compounds, and because of their half-metallic ferromagnetic properties, they are regarded prospective candidates for spintronic applications. [ABSTRACT FROM AUTHOR]

In this article, we have conducted a comprehensive study on the structural, mechanical, electronic, magnetic and thermodynamic properties of the Heusler alloys FeZrTiZ ( Z = A l , G a , G e ). Our investigation utilize the GGA exchange correlational approximation functional. The results of our analysis indicate that among the Y1-, Y2- and Y3-type structures, the Y1-type structure exhibits stability and demonstrates ferromagnetic behavior. Furthermore, mechanical property analysis reveals that all alloys possess ductile characteristics. The analysis of the density of states of the Heusler alloys FeZrTiZ ( Z = A l , G a , G e ) demonstrates the presence of half-metallic nature in all of the alloys. Additionally, the investigated Heusler alloys exhibit integer spin magnetic moments. To study thermodynamic properties, we use quasi-harmonic approximation, which allows to analyze specific heat capacity, thermal expansion, Debye temperature, vibrational free energy, internal energy and entropy of the Heusler alloys FeZrTiZ ( Z = A l , G a , G e ). Overall, our findings provide a clear understanding of the structural, mechanical, electronic, magnetic and thermodynamic characteristics of Heusler alloys FeZrTiZ ( Z = A l , G a , G e ), shedding light on their potential applications in spintronics. [ABSTRACT FROM AUTHOR]

In this study, the WIEN2k code, utilizing the full potential linearized augmented plane wave (FPLAPW) approach within the framework of density functional theory (DFT), explicitly employing the PBEsol approximation, is employed to investigate the fundamental properties of W-doped and (Mo, W) co-doped cubic CeO2. Herein, lattice constants, bulk modulus and cell volumes were evaluated for structural properties. The total density of states (TDOS) for various doped and co-doped CeO2 systems was used to explain the origin of magnetic behavior. The band structure (BS) calculations show that the doped and co-doped materials exhibit semiconductor behavior with a direct bandgap in both spin channels. The calculated total spin magnetic moments of W/CeO2 and (Mo, W)/CeO2 alloys are 2.002 μ B and 4.007 μ B , respectively. Furthermore, the optical absorption shows absorption peaks in the visible range and a redshift. As a result, adding molybdenum and tungsten additives improves the electro-optical properties of previous materials. [ABSTRACT FROM AUTHOR]

Quantum transport properties of normal/ferromagnetic/normal graphene (NG/FG/NG) superlattices exposed to ferromagnetic graphene connected to a gate electrode are investigated via the transfer matrix method. Here, we calculate the role of parameters including well, and barrier width in the spin current. In addition, the Fermi energy and gate voltage effects on raising and tunable spin splitting have been investigated. Calculations demonstrate that the exchange field applied to the region of the ferromagnetic graphene device, by changing the chemical potential, results in an oscillatory behavior. We found that it opens a gap and indicates a metal-insulator phase transition by enhancing unit cells (N = 100). Meanwhile, results reveal that by tuning the gate voltage, we can control the spin currents, as a result, it may allow for the filtering of up or down spins. Further, increasing the barrier width and Fermi energy reveals that the spin current is reversible. Furthermore, this computational research found that quantum modulating behavior by controlling wells, barrier widths, and chemical energy in the device. The results might have potential applications in designing nano-devices and developing spintronic systems. [ABSTRACT FROM AUTHOR]

This review provides a summary of the existing literature on a crucial raw material for the production of isotopically pure semiconductors, which are essential for the development of second-generation quantum systems. Silicon-28-tetrafluoride (28SiF4) is used as an educt for several isotope-engineered chemicals, such as silane-28 (28SiH4) and silicon-28-trichloride (28SiHCl3), which are needed in the pursuit of various quantum technologies. We are exploring the entire chain from the synthesis of 28SiF4 to quantum applications. This includes the chemical properties of SiF4, isotopic enrichment, conversion to silanes, conversion to bulk 28Si and thin films, the physical properties of 28Si (spin neutrality, thermal conductivity, optical properties), and the applications in quantum computing, photonics, and quantum sensing techniques. [ABSTRACT FROM AUTHOR]

The physical properties of perovskite-type materials are sensitive to their chemical composition and crystallographic structure, which makes them highly versatile for various advanced technological applications. In this theoretical study, density functional theory (DFT) is employed to investigate the electronic properties of the perovskite-like material CaTiO3, focusing on the substitution of Ti4+ with the magnetic transition metal Cr4+. The results reveal a systematic increase in the effective magnetic moment and a gradual decrease in the bandgap with increasing Cr4+ content in the CaTi1−xCrxO3 system (x = 0.0, 0.25, 0.5, 0.75, 1.0). The interactions between electronic orbitals associated with Ti-O-Cr inter-octahedral bonds modify the magnetic response of the material, leading to hybridizations between valence and conduction states that alter its semiconductor character. This tunability in electronic and magnetic properties underscores the potential of these materials for applications in spintronics. This study offers novel insights into the design of new magnetic semiconductor materials with tailored functionalities, contributing to the development of next-generation spintronic devices. [ABSTRACT FROM AUTHOR]

In this study, we employ first-principle calculations and the full-potential linearized augmented plane-wave (FLAPW) method to systematically investigate the impact of A-site doping on the properties of CoScO3. By creating nonstoichiometric perovskite compounds of Co1 − xNixScO3 with varying concentrations of Ni ions (x = 0, 0.25, 0.50, 0.75, and 1), we explore changes in the structural, electronic, magnetic, and optical characteristics. Our investigation reveals that all the compounds under consideration adopt a crystalline tetragonal structure. Intriguingly, as the concentration of Ni ions within the A-site increases, a reduction in the total magnetic moment is observed, suggesting a tunable magnetic behavior driven by the dopant ions. Importantly, our results demonstrate that all the doped compounds exhibit a remarkable half-metallic behavior, indicating the potential for efficient spin-dependent transport properties. Moreover, the optical properties of the doped compounds exhibit characteristics that render them suitable candidates for applications in spintronic and photovoltaics. These findings open up avenues for designing novel materials that bridge the gap between magnetic and electronic functionalities. [ABSTRACT FROM AUTHOR]

This research aims to employ a first-principles approach based on density functional theory (DFT) to predict the structural, electronic, and magnetic attributes of CdMX compounds, where M represents Ru , Rh , or Pd , and X represents either S or Se . We utilized the modified Beck-Johnson potential, combined with the generalized gradient approximation ( mBJGGA ), to scrutinize the electronic and magnetic features of these compounds. The results reveal robust magnetic ground states for M -doped CdX . The analysis of spin-polarized band structures and densities of states indicates that CdRuX and CdPdX compounds exhibit half-metallic ferromagnetism, characterized by complete spin polarization of 100% at the Fermi level. Conversely, CdRhX compounds exhibit the properties of ferromagnetic semiconductors. For Ru , Rh , and Pd -doped CdX , an integer-integrated total magnetic moment is observed, corresponding to 4, 3, and 2 μ B , respectively, with the primary contribution stemming from the doping atom and its four nearest neighboring X atoms. This ferromagnetic behavior is attributed to the strong p - d hybridization occurring between the states of the host X ions and the M impurity ion. Consequently, the outcomes of our study render these alloys as suitable materials for possible spintronic devices. [ABSTRACT FROM AUTHOR]

The magnetic characters of VPd2Br4 spinel were calculated using different spin orientations, and electronic properties were investigated using different potential approaches. The ferromagnetic (FM) phase was the most stable magnetic state according to magnetic orientation calculations. The lattice parameter of VPd2Br4 spinel in the FM phase was obtained as 11.17 Å. Elastic analyses showed that the FM phase was mechanically stable. Cauchy's pressure (C12–C44), B/G ratio, and Poisson's ratio (ν) values were obtained as 22.819 GPa, 5.89, and 0.419 at 0 GPa pressure, respectively. Therefore, VPd2Br4 spinel was ductile at 0 GPa pressure. As a result of elastic calculations, Debye temperature was obtained as 136 K. The total magnetic moment value of VPd2Br4 spinel in the FM phase was obtained as 2.00 µB/f.u. The V-atom with a magnetic moment value of 1.868 µB was the most partial contribution to the total magnetic moment. According to electronic properties, minority electron states of VPd2Br4 spinel had semiconductor character, while majority electron states showed metallic character. The band gaps in the minority electron states were calculated as 1.358 eV, 1.705 eV, 2.011 eV, and 2.253 eV according to the GGA, GGA + 1 eV, GGA + 2 eV, and GGA + 3 eV approaches, respectively. These band gaps in the minority electron states and the metallic characters in the majority electron states indicated that VPd2Br4 spinel had 100% spin polarization. Thus, using different approaches, VPd2Br4 spinel was obtained as a true half-metallic material in the FM phase. [ABSTRACT FROM AUTHOR]

High leakage power consumption has become one of the main concerns of data security protection with CMOS device scaling. Spintronic technology is one of the efficient solutions to control circuit leakage power consumption by benefiting from its non-volatility property. Spintronic devices such as magnetic tunnel junctions (MTJs) are also compatible with CMOS transistors and suitable for designing hybrid MTJ/CMOS circuits. Hybrid MTJ/CMOS circuits can be used in many applications, such as logic-in-memory (LiM) and high-security structures. These circuits demonstrate enhanced data security compared to CMOS-based circuits by leveraging their non-volatile feature, making information leakage and data access more challenging. However, these circuits are not completely immune to attacks, and information can be revealed by potent power analysis attacks such as differential power analysis (DPA) and correlation power analysis (CPA). This paper investigates the resistance to side-channel attacks, especially DPA and CPA, for the magnetoresistive RAM (MRAM) and hybrid MTJ/CMOS AND, OR, XOR gates, hybrid MTJ/CMOS full-adder, and multiplexer circuits. Comprehensive post-layout simulation results using 40 nm TSMC CMOS technology, Monte-Carlo results, and values of normalized energy deviation (NED), normalized standard deviation (NSD)), and normalized power deviation (NPD) of PCSA-based MRAM indicate that the power consumption pattern remains constant in circuits with symmetrical structures in the reading phase even in the presence of inevitable process variation, so these circuits are resilient to power attacks and are competent for use in high-security applications such as hardware implementation of encryption algorithms. [ABSTRACT FROM AUTHOR]

The electronic and magnetic features are investigated for doped diluted magnetic semiconductor, specifically magnesium selenide (MgSe). The semiconductor is doped with a single impurity of either zirconium (Zr) or niobium (Nb). To conduct this investigation, a combination of the Korringa-Kohn-Rostoker coherent potential approximation, generalized gradient approximation (GGA) first-principles calculation, and the parametrization method of Pedrew Burke and Ernzerhof (PBE) is used. Our results show that the incorporation of Zr and Nb into the host composite makes a significant contribution to the total magnetic moment of the doped system. The total magnetic moment for M g 1 - x D x S e (D= Nb,Zr) is - 0.58 μ B and - 0.38 μ B for Nb and Zr, respectively, induced by the polarization of the spin at Fermi level ( E F ). Moreover, the ferromagnetic state is stable due to the double exchange mechanism and exhibits a remarkable Curie temperature (Tc) with maximum values of 940 K and 619 K for 2% concentration of Nb and 20% of Zr, respectively. This result leads to interesting magnetic behavior. On the other hand, the double exchange, responsible for short-range interactions mediated by Selenium atoms, arises from the occurrence of p-d orbital hybridization. As a consequence, doping MgSe with Zr and Nb transition metals opens the door to explore and develop new devices in spintronic areas, under room temperature. [ABSTRACT FROM AUTHOR]

This study focuses on investigating the influence of exchange and correlation interactions on the spin polarized electronic structure and magnetic properties of Ga0.75Mn0.25P in the B3 Zinc Blende phase. First-principle calculations were performed by systematically varying the Hartree-Fock (HF) exchange (α) value from 0 to 25% using the onsite exact-exchange functional for the treatment of the correlated electrons. The electronic and magnetic properties unveil that Ga0.75Mn0.25P manifests a half-metallic ferromagnetic behaviour at deferent values of HF exchange. Moreover, as the fraction (α) parameter increases, the band gap increases, leading to modifications in the spin polarized band structures. Additionally, our investigations indicate that exchange and correlation interactions cause an increase in the lattice parameter and volume of the compound. Furthermore, these interactions result in a decrease in the magnetic moments of P and Ga atoms, while the Mn moments increase. These findings provide valuable insights into the behavior of Ga0.75Mn0.25P and offer potential applications in the design of spintronic devices. [ABSTRACT FROM AUTHOR]

The aim is to tune the stability, as well as electronic and magnetic characteristics of zigzag α‐borophene nanoribbons (ZαBNRs) based on density functional theory. For this reason, the bare ZαBNR and its passivated edges by a single nitrogen atom (N‐ZαBNR) and also Mn‐ and Cr‐doped N‐ZαBNR is investigated. The results indicate that the nanoribbon becomes more stable by passivating the edges of the structure. Furthermore, the calculated electronic structures show that the Cr atom can remove the band gap of N‐ZαBNRs and turn it into metal. Besides, it can create magnetic properties in this structure. The Cr‐ and Mn‐doped N‐ZαBNR turn it into magnetic metal and diluted magnetic semiconductors, respectively. The results reveal a high Curie temperature of more than 700K for Cr‐ and Mn‐doped N‐ZαBNRs, indicating maybe good room‐temperature ferromagnetic material for spintronic applications in the future. [ABSTRACT FROM AUTHOR]

Recent development in neural networks (NNs) has led to their widespread use in critical and automated decision-making systems, where uncertainty estimation is essential for trustworthiness. Although conventional NNs can solve many problems accurately, they do not capture the uncertainty of the data or the model during optimization. In contrast, Bayesian neural networks (BNNs), which learn probabilistic distributions for their parameters, offer a sound theoretical framework for estimating uncertainty. However, traditional hardware implementations of BNNs are expensive in terms of computational and memory resources, as they (i) are realized with inefficient von Neumann architectures, (ii) use a significantly large number of random number generators (RNGs) to implement the distributions of BNNs, and (iii) have a substantially greater number of parameters than conventional NNs. Computing-in-memory (CiM) architectures with emerging resistive non-volatile memories (NVMs) are promising candidates for accelerating classical NNs. In particular, spintronic technology, which is distinguished by its low latency and high endurance, aligns very well with these requirements. In the specific context of Bayesian neural networks (BNNs), spintronics technologies are very valuable, thanks to their inherent potential to act as stochastic or as deterministic devices. Consequently, BNNs mapped on spintronic-based CiM architectures could be a highly efficient implementation strategy. However, the direct implementation on CiM hardware of the learned probabilistic distributions of BNN may not be feasible and can incur high overhead. In this work, we propose a new Bayesian neural network topology, named SpinBayes, that is able to perform efficient sampling during the Bayesian inference process. Moreover, a Bayesian approximation method, called in-memory approximation, is proposed that approximates the original probabilistic distributions of BNNwith a distribution that can be efficiently mapped to spintronic-based CiM architectures. Compared to state-of-the-art methods, the memory overhead is reduced by 8x and the energy consumption by 80x. Our method has been evaluated on several classification and semantic segmentation tasks and can detect up to 100% of various types of out-of-distribution data, highlighting the robustness of our approach, without any performance sacrifice. [ABSTRACT FROM AUTHOR]

Currently, static circuit power is becoming a major concern, dominating the total power consumption due to the scaling down of CMOS technology. The smaller sizes drastically affect the leakage current, which integrated circuit designers attempt to overcome this issue. Hence, several methods and technologies have been proposed to prevail this phenomenon. One of these methods is using memory structures in logic designs. A Hybrid MTJ/CMOS circuit is one of these promising techniques to design low-power nonvolatile circuits with power gating ability and low overhead for reconfigurable possibilities. In this paper, we have proposed a fully nonvolatile, low-power Full-Adder based on MTJs that uses the spin transfer torque method assisted by the spin hall effect. Simulation results of these designs by HSPICE show that they can work fast with low-power consumption compared to other state-of-the-art nonvolatile full-adders. [ABSTRACT FROM AUTHOR]

The exciting properties of multi-valued logic (MVL) in overcoming the limitations of binary systems have led to widespread research on this topic. Considering various types of MVL, quaternary logic is more compatible with the existing binary systems. This paper proposes a nonvolatile quaternary flip-flop (NQFF) based on the unique features of the carbon nanotube field-effect transistors (CNTFETs) and magnetic tunnel junctions (MTJs). The proposed NQFF utilizes Spin-Hall effect (SHE)-assisted spin-transfer torque (STT) MTJs to provide nonvolatility with lower write energy, and multi-Vt gate-all-around (GAA) CNTFETs offer higher performance. On the other side, due to the usage of a shadow latch and the design of the proposed circuit, the delay of MTJ switching does not affect the delay of the whole circuit. The simulation results show that the proposed NQFF offers 50% lower PDP when the system is idle for only 25% of its total operational time. [ABSTRACT FROM AUTHOR]

Chirality is an attribute based on the structural geometry of materials, which confers a distinctive energy band structure for intriguing optical, electronic, and spintronic properties. Recent studies on chirality encountered in perovskite(‐inspired) halides (PiHs) have drawn increasing attention, not only because of the large chemical diversity of PiHs seen at molecular, nanoscopic, and microscopic levels, but also due to the observation of various emergent properties for multifunctional device applications. Herein hierarchical chiral origin factors of PiHs, involving intercalation, substitution, and distortion at the intra‐crystal level; modification at the crystal interface level; and micro‐design beyond the crystal level are first discussed. Then, updated progress in synthesis and characterization methods of chiral PiHs is reviewed, featuring intriguing structures that distinguish chiral PiHs from other semiconductors and chiral materials. Furthermore, representative examples exploiting emergent properties of chiral PiH for achieving versatile device functions are examined. Finally, perspectives on challenges and opportunities in leveraging the chirality in PiHs for transformative device applications are provided. [ABSTRACT FROM AUTHOR]

Co 2 FeSi Heusler alloys have attracted a lot of attention due to their interesting properties for various technological applications. In this study, we present the results of ab-initio calculations of the electronic, structural and magnetic properties using generalized gradient approximations (GGA and GGA + U). The energies obtained from GGA are used to calculate the magnetic coupling and establish an effective Hamiltonian. Additionally, we utilized mean-field theory and Monte Carlo simulation to evaluate physical properties such as magnetization, susceptibility and critical exponent of the material from the effective Hamiltonian. The results indicate that Co2FeSi, which exhibits a half-metallic behaviour, may be suitable for use in spintronic applications. [ABSTRACT FROM AUTHOR]

The purpose of this study is to conduct theoretical investigations on the electronic, structural and magnetic properties of lithium niobate (LiNbO3) doped with different concentrations of the transition metal chromium (Cr). All properties of LiNb1−xCrxO3 compounds (x = 0.25, 0.50 and 0.75) are achieved with spin-polarized density functional theory by the GGA-PBE and the TB-mBJ approximations. To ensure the stability of the LiNb1−xCrxO3 quaternary alloy in the ferromagnetic state, the total energy released from the optimized structure and the defect formation energy were calculated. The classical Heisenberg model estimated the Curie temperature of the compounds. The material studied exhibits a 100% spin-polarized semi-metallic ferromagnetism behaviour. In all compounds, the data of the magnetic moment demonstrated that the chromium impurity atom is the most important source by comparison with the Nb and Li, which have minor contributions. In addition, the magnetic moment of the Cr atoms decreases with doping; this comes from the p–d hybridization between the Cr-3d and O-2p states. The half-metal gap (GHM), the most important factor in spintronics applications, was also calculated. In addition, to assess the effects of the exchange separation process, the crystal field separation energy, the exchange separation parameters, and the exchange constants N0α, N0β, and ΔEC, ΔEV are predicted. [ABSTRACT FROM AUTHOR]

The injection of pure spin current into the non‐magnetic layer plays a crucial role in transmitting, processing, and storing data information in the realm of spintronics. To understand broadband molecular spintronics, pyrene oligomer film (≈20 nm thickness) was prepared using an electrochemical method forming indium tin oxide (ITO) electrode/pyrene covalent interfaces. Permalloy (Ni80Fe20) films with different nanoscale thicknesses were used as top contact over ITO/pyrene layers to estimate the spin pumping efficiency across the interfaces using broadband ferromagnetic resonance spectra. The spintronic devices are composed of permalloy/pyrene/ITO orthogonal configuration, showing remarkable spin pumping from permalloy to pyrene film. The large spin pumping is evident from the linewidth broadening of 5.4 mT at 9 GHz, which is direct proof of spin angular momentum transfer across the interface. A striking observation is made with the high spin‐mixing conductance of ≈1.02×1018 m−2, a value comparable to the conventional heavy metals. Large spin angular moment transfer was observed at the permalloy‐pyrene interfaces, especially at the lower thickness of permalloy, indicating a strong spinterface effect. Pure spin current injection from ferromagnetic into electrochemically grown pyrene films ensures efficient broadband spin transport, which opens a new area in molecular broadband spintronics. [ABSTRACT FROM AUTHOR]

The injection of pure spin current into the non‐magnetic layer plays a crucial role in transmitting, processing, and storing data information in the realm of spintronics. To understand broadband molecular spintronics, pyrene oligomer film (≈20 nm thickness) was prepared using an electrochemical method forming indium tin oxide (ITO) electrode/pyrene covalent interfaces. Permalloy (Ni80Fe20) films with different nanoscale thicknesses were used as top contact over ITO/pyrene layers to estimate the spin pumping efficiency across the interfaces using broadband ferromagnetic resonance spectra. The spintronic devices are composed of permalloy/pyrene/ITO orthogonal configuration, showing remarkable spin pumping from permalloy to pyrene film. The large spin pumping is evident from the linewidth broadening of 5.4 mT at 9 GHz, which is direct proof of spin angular momentum transfer across the interface. A striking observation is made with the high spin‐mixing conductance of ≈1.02×1018 m−2, a value comparable to the conventional heavy metals. Large spin angular moment transfer was observed at the permalloy‐pyrene interfaces, especially at the lower thickness of permalloy, indicating a strong spinterface effect. Pure spin current injection from ferromagnetic into electrochemically grown pyrene films ensures efficient broadband spin transport, which opens a new area in molecular broadband spintronics. [ABSTRACT FROM AUTHOR]

High-speed and low-power area-efficient memory solutions are in high demand in today's smart and internet environment. To program and store data and its associated information, it has grown as a fantastic concept to replace charge in semiconductor devices with electron spin. By further eliminating power dissipation, this leads to the development of "green electronics," a field of technology that is both energy and chip space efficient. A sort of spintronic device created for potential energy-efficient applications is the magnetic tunnel junction (MTJ) device controlled by spin orbit torques (SOTs). A three-terminal MTJ device with perpendicular to the plane magnetization may operate more quickly and efficiently thanks to the available spin orbit torques (PMTJ). The design of a novel modified non-volatile master slave flip flop (NVMSFF) for register memory array architectures is presented in this study. It is low-power, high-speed, and area-efficient. The NVMSFF design uses a hybrid approach that combines CMOS 45 nm technology with a Verilog-A Model-based SOT-PMTJ circuit that uses spintronics. Additionally, the planned NVMSFF and current NVSFF were used in the design of the 4 × 4 and 8 × 8 memory arrays. The suggested updated NVMSFF was shown to have a lower latency, use less space, and dissipate less power. Additionally, it was discovered that Designed Memory arrays were space and energy efficient. [ABSTRACT FROM AUTHOR]

Current-induced field-free magnetization switching in single-layer films has been widely investigated for the application of spin–orbit torque (SOT) drivers in low-power, high-density, and nano-sized memory. In this paper, we report field-free SOT switching with threefold angle dependence in A1 disordered single-layer CoPt using the MgO (111) substrate. It is found that the magnetization could not switch in the absence of an external in-plane magnetic field when the current was flowing in the direction of the mirror symmetry high-symmetry axis ([11–2]). While along the direction of the low-symmetry axis ([1–10]) which destroyed the mirror symmetry to the greatest extent, field-free switching could be performed, and the switching ratio was up to 30%. This was mainly attributed to the composition gradient-induced in-plane inversion asymmetry and the low symmetry at the interface of Co/Pt broken out-of-plane inversion. Furthermore, CoPt devices with nanoscale thickness exhibited stable multistate magnetic switching behavior without an external magnetic field, and simultaneously nonlinear synaptic characteristics were obtained. A neural network was established, in which the synaptic weights between the hidden layer and the output layer are updated by using the resistance state of SOT synaptic devices, and the network could achieve about 90.54% recognition accuracy when applied to MNIST's handwritten digital dataset. This work confirmed that a field-free SOT switch could be realized in single-layer CoPt, which provided theoretical guidance and data support for spin devices. [ABSTRACT FROM AUTHOR]

Between the ferromagnetic semiconductors of the III‐V group, the transition metals (TMs) doped gallium nitride (Ga, TM)N diluted magnetic semiconductor (DMS) shows the most well‐understood and promising applications in spintronic, due to its high Curie temperature. In this research, electronic and magnetic properties of pure armchair (3, 3) and zigzag (5, 0) gallium nitride nanotubes (GaNNTs) and doped with TMs are investigated using the spin‐polarized density functional theory. The spin‐polarized DOS revealed that pure zigzag and armchair GaNNTs are nonmagnetic semiconductors with a direct and indirect bandgap, respectively, in contrast, TMs doped GaNNTs are DMS or half metals (HM). Our results show a high Curie temperature of more than 823 K for Cr and Mn doping, indicating may be good room‐temperature ferromagnetic material for spintronic applications in the future. 11% Cr and Mn atoms doped (3, 3) GaNNT are HM with 100% spin polarization and appear to be good candidates for spintronic applications and especially as spin filter devices. [ABSTRACT FROM AUTHOR]

We report here the structural, optical, photoluminescence (PL), and magnetic investigation of Zn1−x−yFexMyO nanoparticles. The lattice constants and crystallite size are decreased by Fe, followed by a further decrease up to (Fe + M) = 0.30. A compressive stress is approved and the size of particle is between 180 and 277 nm and follows the sample order of ZnO, (Fe + Cu), (Fe + Ni), and Fe. Although a single value of energy gap (Eg) is found for pure and Fe-doped ZnO, two values of Eg (Egh and Egl) are found for the co-doped samples. The Eg is generally increased by Fe, followed by a further increase for the Cu-series, whereas it is decreased for the Ni-series. The refractive indices nK and nT proposed by different methods are generally decreased by Fe, followed by a further decrease for both series. Although Fe doped ZnO depressed the density of carriers (N/m*), it increased again for the co-doped samples. The residual dielectric constant ϵL is decreased by Fe, followed by an increase for the Cu-series, but it is decreased for the Ni-series. The loss factor tan δ increases slightly with Fe, followed by an increase for the Ni-series, but it decreases in the Cu-series. A significant depression of optical conductivity σopt by Fe was obtained, followed by a further decrease which is higher for the Cu-series. The PL shows four visible emissions. Interestingly, an IR emission at about 825 nm is only obtained for the co-doped samples. Furthermore, the blue emission (Iblue) was higher than UV (IUV), [(Iblue/IUV) > 1], but it is greater for the Ni series than the Cu. Although ZnO exhibits diamagnetic behavior, the Fe and co-doped samples exhibit ferromagnetic with higher magnetization for the Ni-series than the Cu. The current results recommend the co-doped samples in nanoscale for some of advanced devices. [ABSTRACT FROM AUTHOR]

A spin-topological electronic valve was discovered in a Ni/hBN–graphene–hBN/Ni magnetic junction to control the in-plane conductance of graphene. By manipulating the mass-gapped Dirac cone (MGDC) of graphene's topology using the magnetic proximity effect, the spin-topological electronic valve was made possible. The first-principles investigation was conducted to show how the mechanism of graphene's MGDC is controlled. Twelve stacking configurations for the anti-parallel configuration (APC) and parallel configuration (PC) of the magnetic alignment of Ni slabs were calculated using spin-polarized density functional theory. Three groups can be made based on the relative total energy of the 12 stacking configurations, which corresponds to a van der Waals interaction between hBN and graphene. Each group exhibits distinctive features of graphene's MGDC. The configuration of the Ni(111) surface state's interaction with graphene as an evanescent wave significantly impacts how the MGDC behaves. By utilizing the special properties of graphene's MGDC, which depend on the stacking configuration, a controllable MGDC using mechanical motion was proposed by suggesting a device that can translate the top and bottom Ni(111)/hBN slabs. By changing the stacking configuration from Group I to II and II to III, three different in-plane conductances of graphene were observed, corresponding to three non-volatile memory states. This device provides insight into MJs having three or more non-volatile memory states that cannot be found in conventional MJs. [ABSTRACT FROM AUTHOR]

Magnetic 2D materials have attracted considerable attention for their significant potential application in spintronic. In this work, the effect of substitutional doping of 3d‐transition metals such as Co, Cr, Mn, and Fe on the magnetic and electronic properties of boron nitride nanosheet (BNNS) was studied based on the spin‐polarized density functional theory. The results revealed that the non‐magnetic and semiconducting behavior of BNNS can be altered by magnetically active dopants. The spin‐polarized density of states suggests that pure BNNS is a nonmagnetic semiconductor with a direct bandgap while transition metals doped BNNS are dilute magnetic semiconductors or half metals (HM). Co doping shows the most stable ferromagnetic phases in the nanosheet. A pair of Mn and Co atoms doped BNNS in edge structure show HM property with 100% spin polarization and seem to be good candidates for spintronic applications and especially as spin filter devices and spin current injectors. [ABSTRACT FROM AUTHOR]

The structural, half-metallic, and elastic characteristics of XZrAs (X = Cr, Mn, and V) half-Heusler compounds were theoretically calculated using the WIEN2k code. For the term of the potential exchange and correlation (XC), we calculated structural, electronic, and magnetic properties using the generalized gradient approximation (GGA). The type 1 arrangement in ferromagnetic (FM) phases is more energetically stable than other type arrangements in all compounds. The spin-up electrons of both XZrAs (X = Cr, Mn) half-Heusler compounds in the type III structure are semiconducting with energy gaps, whereas the spin-dn electrons are metallic. Research has also been done on the VZrAs compound, which exhibits metallic characteristics in both type I and type III structures. XZrAs (X = Cr, Mn, and V) half-Heusler compounds are elastically stable and ductile, according to calculated Cij elastic constants. Finally, at equilibrium lattice constants a = 6.1196 A° for MnZrAs and 6.142 A° for CrZrAs, real half-metal ferromagnetic materials (HMF) were produced from XZrAs (X = Cr, Mn) half-Heusler compounds within 3 µB and 2µB, respectively. [ABSTRACT FROM AUTHOR]

The magnetic properties were investigated for C- and P-implanted MgO single crystals, which were irradiated by 80 keV C and P ions with the dose of 3 × 1017 ions/cm2. The magnetic properties of pristine MgO were apparently changed by C and P ion implantation. Room temperature ferromagnetism was presented in the C-implanted sample, while the P-implanted sample only displayed paramagnetism at 20 K. For the purpose of clarifying the correlation between the magnetic properties and microstructure, a comparative study was carried out using experimental and theoretical methods in both C and P ion-implanted samples. The defect types were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, photoluminescence, and absorption spectrum. The existence of intrinsic (Mg vacancies, O vacancies) and extrinsic (C-related and P-related) defects were verified by the experimental results. The magnetic properties induced by various single and composite defects were studied by first-principle calculations. The calculation results indicated that the configuration of VMg (Mg vacancy) + CO (C substitute O defect) was a key factor for the inducing ferromagnetic properties in C-implanted MgO. For the case of the P-implanted MgO, the configuration of P-related defects and intrinsic vacancies can only contribute to the total moment value but cannot induce ferromagnetism. [ABSTRACT FROM AUTHOR]

Spintronic metal thin films excited by femtosecond laser pulses have recently emerged as excellent broadband sources of terahertz (THz) radiation. Unfortunately, these emitters transmit a significant proportion of the incident excitation laser, which causes two issues: first, the transmitted light can interfere with measurements and so must be attenuated; second, the transmitted light is effectively wasted as it does not drive further THz generation. Here, we address both issues with the inclusion of a high-reflectivity (HR) coating made from alternating layers of SiO2 and Ta2O5. Emitters with the HR coating transmit less than 0.1% of the incident excitation pulse. Additionally, we find that the HR coating increases the peak THz signal by roughly 35%, whereas alternative attenuating elements, such as cellulose nitrate films, reduce the THz signal. To further improve the emission, we study the inclusion of an anti-reflective coating to the HR-coated emitters and find the peak THz signal is enhanced by a further 4%. [ABSTRACT FROM AUTHOR]

Through first-principles investigation, two new Mn2-based full-Heusler alloys, Mn2HfSi and Mn2HfGe, have been studied using the full-potential linearized augmented plane wave (FP-LAPW) approach as implemented in the WIEN2k code. Our study focuses on these compound's stability (thermodynamic, dynamic, and mechanical), electronic, and magnetic properties. The L21 (Cu2MnAl-type) structure is shown to be more energetically favorable than the XA (Hg2CuTi-type) structure for both compounds, Mn2HfX (X = Si and Ge). We demonstrate that Mn2HfX (X = Si and Ge) are stable through the calculations of cohesive, formation energies, phonon dispersion curves, and the elastic constants, with the illustration of 3D and 2D bulk and Young's moduli. Using GGA and GGA-mBJ calculations show that Mn2HfX (X = Si and Ge) are half-metallic ferrimagnets (HMFs), with indirect band gap through the altered Becke-Johnson (mBJ), GGA approximation: 0.689 eV for Mn2HfSi and 0.520 eV for Mn2HfGe. Furthermore, the electrons at the Fermi level (EF) were fully spin-polarized. The total magnetic moment in these two compounds was found to have an integer value of 2 µB per formula, which complies with the Slater-Pauling rule Mtot = Ztot − 24. These compounds are favorable materials for spintronic applications. It was revealed that Mn2HfSi and Mn2HfGe maintained their half-metallicity for lattice constants in the range of 5.7–6.2 Å and 5.75–6.2 Å, respectively. [ABSTRACT FROM AUTHOR]

The structural, electronic, and magnetic properties of a new series CoRhZrZ quaternary Heusler were investigated theoretically by using the density of function theory calculation. All the compounds were found to be stable at the ferromagnetic phase. The magnetic moments of the compound show a positive value ranging from 1 to 2 μB. In addition, the electronic structure of CoRhZrSi shows a large value of the half‐metallic band gap of 0.34 eV. This reflects the high thermal stability of the compound at high temperatures and allowing for a wide range of applications of this material in varying domains, especially those requiring high thermal stability such as the oil and gas sectors, geological applications, and space applications. [ABSTRACT FROM AUTHOR]

With the incredible discovery of graphene (Gr), all of the properties studied to date suggest that it has promising applications in the development of semiconductor, spintronic, insulating, and polymer materials. However, efforts are still underway to fully understand the nature of metal–graphone(GrH) interaction in order to offer better scope for tuning the electronic and magnetic properties, which can be performed by intercalation of atoms via metal support on graphene. We chose metal atoms belonging to the s and p blocks, namely Na and Al, respectively, as the intercalating atoms. Herein, the maximum coverage of a monolayer of Na and Al was comparatively studied on a Ni(111) surface. Significant changes in the magnetic and electronic properties at the Ni(111)/graphone interface were observed upon intercalation. Of the two intercalating metal atoms, Na proved to be more effective, such that the magnetic properties of the surface Ni were only slightly decreased, and the graphone also showed better magnetic properties than in the absence of Na. [ABSTRACT FROM AUTHOR]

This paper reported on the theoretical investigations with first principle calculations on the electronic and band structure properties of Cr-doped GeO2 rutile. Firstly, it discussed the half-metallic characteristics of rutile GeO2 (r-GeO2) bulk crystal when this latter is doped with 3d-Cr transition metal. Secondly, and to understand the impact of doping Cr impurity, three amounts of Cr of 2, 6 and 10% were inserted in the r-GeO2 lattice which showed how doping can improve the magnetic properties of the obtained dilute magnetic semiconductor. The theoretical calculations were performed in the general framework of the density functional theory within the Korringa–Kohn–Rostoker approach combined with the coherent potential approximation. We adopted the local density approximation (LDA) as well as the self-interaction corrected LDA (LDA-SIC) to account for the exchange and correlation in the strong correlated electron systems. Based on calculations within LDA and LDA-SIC approximations, it was found that the compound behaves as half-metal material. Moreover, we have studied the interaction responsible of magnetism using both LDA and LDA-SIC approximations. In addition, we calculated the exchange coupling parameters of the classical Heisenberg model and studied the X-ray absorption spectrum at the K-edge of Ge1−xCrxO2. The obtained values of Curie temperature were found above the ambient value once doping concentration exceeds 6%. Hence, it can be inferred that Cr-doped r-GeO2 presents a good potential as a practical spintronic material when the doping concentration is greater than or equal to 6%. [ABSTRACT FROM AUTHOR]

In this work, we have successfully fabricated nanocrystalline Co2MnSi Heusler alloy glass-coated microwires with a metallic nucleus diameter (dnuclei) 10.2 ± 0.1 μm and total diameter 22.2 ± 0.1 μm by the Taylor–Ulitovsky technique for the first time. Magnetic and structural investigations have been performed to clarify the basic magneto-structural properties of the Co2MnSi glass-coated microwires. XRD showed a well-defined crystalline structure with a lattice parameter a = 5.62 Å. The room temperature magnetic behavior showed a strong in-plane magnetocrystalline anisotropy parallel to the microwire axis. The M-H loops showed unique thermal stability with temperature where the coercivity (Hc) and normalized magnetic remanence exhibited roughly stable tendency with temperature. Moreover, quite soft magnetic behavior has been observed with values of coercivity of the order of Hc = 7 ± 2 Oe. Zero field cooling and field cooling (ZFC-FC) magnetization curves displayed notable irreversible magnetic dependence, where a blocking temperature (TB = 150 K) has been observed. The internal stresses generated during the fabrication process induced a different magnetic phase and is responsible for the irreversibility behavior. Moreover, high Curie temperature has been reported (Tc ≈ 985 K) with unique magnetic behavior at a wide range of temperature and magnetic fields, making it a promising candidate in magnetic sensing and spintronic applications. [ABSTRACT FROM AUTHOR]

Samples of (110), (100), and (111) MgO single crystals were implanted with 70 keV N ions at room temperature. All as-implanted samples showed room temperature hysteresis in magnetization loops. The observed saturation magnetization (Ms) was 0.79 × 10−4 emu/g, 1.28 × 10−4 emu/g, and 1.5 × 10−4 emu/g for (110), (100) and (111) orientation implanted-MgO and follows the relation Ms(111) > Ms(100) > Ms(110), indicative of crystalline orientation-dependent ferromagnetism in N-implanted MgO. The samples were characterized by X-ray photoelectron spectroscopy (XPS), high resolution X-ray diffraction (HRXRD), reciprocal space mapping (RSM), and photoluminescence (PL). The results indicated that the amount of N-substitute-O and N-interstitial defects in these three N-implanted MgO samples showed the same changing tendency as compared with Ms data. Thus, we conclude that the N-substitute-O and N-interstitial defects may play a crucial role in controlling the N+-implanted-induced ferromagnetism. [ABSTRACT FROM AUTHOR]

Summary: In this work, density functional theory and molecular dynamics (MD) calculations are performed on TiOx (ie, x = 1‐3) doped γ‐graphyne to modify its structural, opto‐electronic, and spintronic characteristics. Obtained negative binding energies (Eb) values and MD calculations suggest that TiOx substitution in γ‐graphyne is thermodynamically stable. Furthermore, the direction of charge transfer occurs from TiO1(2) clusters to the γ‐graphyne, whereas in case of TiO3, γ‐graphyne lends its charge carriers to impurity cluster. TiO2(3) cluster doping converts nonmagnetic γ‐graphyne to a magnetic material having ~2.00 μB magnetic moment. TiO doped γ‐graphyne displays nonmagnetic narrow band indirect semiconductor behavior at M‐point with ~1.0 eV band gap. Since TiO2(3) cluster doped γ‐graphynes carried magnetic behavior, hence displayed spin polarized band structures. During spin down band, TiO2 doped γ‐graphyne carries ~0.7 eV band gap having n‐type dopant nature. Similarly, during spin up channel, TiO3 doped γ‐graphyne carries ~0.9 eV direct band gap semiconductor behavior. Blue shift appears in absorption and extinction coefficient plots after TiOx substitution in γ‐graphyne. Likewise, static reflectivity and refractive index parameters are improved having maximum of 0.65 and 8 peak intensities, respectively. Our obtained results suggest a viable way forward for making functional hybrid γ‐graphynes to be used in opto‐electronic and spintronic device applications. [ABSTRACT FROM AUTHOR]

The concept of using single molecules as functional building blocks in electronic circuitry represents the ultimate device miniaturization and has garnered tremendous attention from physics, chemistry, and engineering. Recent advances in single-molecule junction techniques have enabled direct investigation of charge transport in a quasi-one-dimensional conduction channel composed of an individual molecule. One of the main research focuses over the past decade has been to understand the conductance switching effect of single molecules as it is essential for developing molecular-scale optoelectronics, computing, and sensing applications. In this perspective, we highlight the established physical and chemical mechanisms for single-molecule conductance switching behavior and examine the associated stimuli in single-molecule junction systems. [ABSTRACT FROM AUTHOR]

Renewed interest in cryogenic transmission electron microscopy (cryo-TEM) for physical and materials science research has emerged in recent years after being awarded the Nobel Prize in 2017 for its success in structural biology. In this perspective, the recent advancement in cryo-TEM techniques and its applications in the research of emerging materials for quantum information sciences and clean energy technologies are summarized and discussed in relevant topical areas. Cryo-TEM for quantum materials is specifically focused on exotic electronic states in strongly correlated systems and novel topological spin textures in spintronic materials. For energy-related application, the focus is mainly towards the cryo-TEM characterization of electron radiation sensitive materials, including alkali metals and compounds in batteries, highly porous metal–organic frameworks, and hybrid halide perovskites in photovoltaic solar cells. The challenges and outlook on the future cryo-TEM developments are also provided. [ABSTRACT FROM AUTHOR]

The magnetic tunnel junction is the heart of the STT-MRAM memory. The MTJ is a spintronic device, which is used to store and read the data. With the advancement, most of the work is done online and a useful device is needed in order to store the data. Hence, it is important to design a promising device to store the data for a long time without any damage or loss of information. In this paper, first, we use the MTJ LAB simulator to check the important parameters such as TMR, resistance, and STT components and check how these parameters change for different oxide thicknesses. After this, the device was hybrid with the CMOS for 1-bit STT-MRAM and the results were drawn. So, in this paper, the main focus is to select appropriate oxide thickness and t ox = 0. 8 5 nm is used to get better TMR ratio, resistance, and STT-components. [ABSTRACT FROM AUTHOR]

This study uses the density functional theory method to accurately predict structural, electronic, magnetic, elastic, thermal and thermoelectric properties for two new half-Heusler RbCrSb and RbCrAs compounds. The exchange and correlation potential is treated by employing generalized gradient approximation of Perdew–Burke–Ernzerhof (GGA-PBE), Tran–Blaha-modified Becke–Johnson exchange potential (TB-mBJ) and PBE-GGA + U approaches, where U is the Hubbard on-site Coulomb interaction correction. Structural results reveal that RbCrSb and RbCrAs alloys are energetically stable in type 3 structure FM state. The negative formation and cohesive energies confirm the possibility of their experimental realization. Electronic and magnetic properties show that both compounds exhibit half-metallic character and integer magnetic moments of 4 μB following the Slater–Pauling rule. Elastic calculations unveil that both compounds fulfill the mechanical stability criteria and are anisotropic and ductile in nature. The thermodynamic properties show that the selected materials can be employed under high pressures and high temperatures. Thermoelectric results suggest that RbCrX (with X = Sb, As) exhibits high figure of merit (ZT) values close to the unity at room temperature. Consequently, our new half-Heusler compounds RbCrSb and RbCrAs will be beneficial for thermoelectricity as well as for spintronic device applications. [ABSTRACT FROM AUTHOR]

Using zone calculations in the FLAPS (the full-potential linearized augment- ed-plane-waves) model, information is obtained on the energy, charge and spin characteristics of Pt1-xMexMnSb alloys (Me = Ni, Au, x = 0.0--1.0). As established, with an increase in the concentration of nickel or gold atoms the interatomic spatial density of electrons decreases, covalent bonds weaken and the binding energies of atoms in alloys decrease. As found, the dominant con- tributions to the formation of magnetic moments are made by 3d electrons of manganese atoms, and the polarization of electrons at Fermi levels depends on the composition of alloys. [ABSTRACT FROM AUTHOR]

Proximity effect, which is the coupling between distinct order parameters across interfaces of heterostructures, has attracted immense interest owing to the customizable multifunctionalities of diverse 3D materials. This facilitates various physical phenomena, such as spin order, charge transfer, spin torque, spin density wave, spin current, skyrmions, and Majorana fermions. These exotic physics play important roles for future spintronic applications. Nevertheless, several fundamental challenges remain for effective applications: unavoidable disorder and lattice mismatch limits in the growth process, short characteristic length of proximity, magnetic fluctuation in ultrathin films, and relatively weak spin–orbit coupling (SOC). Meanwhile, the extensive library of atomically thin, 2D van der Waals (vdW) layered materials, with unique characteristics such as strong SOC, magnetic anisotropy, and ultraclean surfaces, offers many opportunities to tailor versatile and more effective functionalities through proximity effects. Here, this paper focuses on magnetic proximity, i.e., proximitized magnetism and reviews the engineering of magnetism‐related functionalities in 2D vdW layered heterostructures for next‐generation electronic and spintronic devices. The essential factors of magnetism and interfacial engineering induced by magnetic layers are studied. The current limitations and future challenges associated with magnetic proximity‐related physics phenomena in 2D heterostructures are further discussed. [ABSTRACT FROM AUTHOR]

For the ultimate goal of adjusting the physical properties of the tin-carbide (SnC) semiconductor, a meticulous theoretical study based on density functional theory (DFT) and Korringa–Kohn–Rostoker (KKR) method combined with coherent potential approximation (CPA) on transition metals substitution is investigated. Iron (Fe) and chromium (Cr) ions have been chosen for their interesting magnetic properties (spin moment, Curie temperature). A value x corresponding to the substitution concentration is varied between 2% and 24% for both S n 1 - x C r x C and S n 1 - x F e x C compound types. All S n 1 - x F e x C compounds show a half-metallic ferromagnetic nature, while a similar behavior is also revealed for S n 1 - x C r x C compounds with x up to 12. Our self-consistent (SCF) spin-polarized calculations findings revealed that the main contributions to the net magnetization of our compound originate from Fe and Cr ions, with the partial spin moment of Fe is 3.68 μ B for 24 % and is around 2.4 μ B for Cr. The mean field approximation indicates that the Curie temperature reaches its highest value of 502.86K for Fe at the x-value of 12% , whereas with Cr substitution, the greatest value of 712K is found at x=24%. These findings show that S n 1 - x C r x C and S n 1 - x F e x C compounds are promising for spintronics applications. [ABSTRACT FROM AUTHOR]

Magnetite (Fe3O4) nanoparticles (NPs) and SiO2-coated Fe3O4 nanoparticles have successfully been synthesized using co-precipitation and modified Stöber methods, respectively. The samples were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, high-resolution transmission electron microscopy (HRTEM), vibrating sample magnetometer (VSM) techniques, X-ray absorption spectroscopy (XAS), and X-ray magnetic circular dichroism (XMCD). XRD and FTIR data confirmed the structural configuration of a single-phase Fe3O4 and the successful formation of SiO2-coated Fe3O4 NPs. XRD also confirmed that we have succeeded to synthesize nano-meter size of Fe3O4 NPs. HRTEM images showed the increasing thickness of SiO2-coated Fe3O4 with the addition of the Tetraethyl Orthosilicate (TEOS). Room temperature VSM analysis showed the magnetic behaviour of Fe3O4 and its variations that occurred after SiO2 coating. The magnetic behaviour is further authenticated by XAS spectra analysis which cleared about the existence of SiO2 shells that have transformed the crystal as well as the local structures of the magnetite NPs. We have performed XMCD measurements, which is a powerful element-specific technique to find out the origin of magnetization in SiO2-coated Fe3O4 NPs, that verified a decrease in magnetization with increasing thickness of the SiO2 coating. Magnetite (Fe3O4) nanoparticles (NPs) and SiO2-coated Fe3O4 nanoparticles have successfully been synthesized using co-precipitation and modified Stöber methods, respectively. The samples were characterized using X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, high-resolution transmission electron microscopy (HRTEM), vibrating sample magnetometer (VSM) techniques, X-ray absorption spectroscopy (XAS), and X-ray magnetic circular dichroism (XMCD). XRD and FTIR data confirmed the structural configuration of a single-phase Fe3O4 and the successful formation of SiO2-coated Fe3O4 NPs. XRD also confirmed that we have succeeded to synthesize nano-meter size of Fe3O4 NPs. HRTEM images showed the increasing thickness of SiO2-coated Fe3O4 with the addition of the Tetraethyl Orthosilicate (TEOS). Room temperature VSM analysis showed the magnetic behaviour of Fe3O4 and its variations that occurred after SiO2 coating. The magnetic behaviour is further authenticated by XAS spectra analysis which cleared about the existence of SiO2 shells that have transformed the crystal as well as the local structures of the magnetite NPs. We have performed XMCD measurements, which is a powerful element-specific technique to find out the origin of magnetization in SiO2-coated Fe3O4 NPs, that verified a decrease in magnetization with increasing thickness of the SiO2 coating. [ABSTRACT FROM AUTHOR]

To reduce the switching delay, area overhead, and power consumption in the magnetic tunnel junction (MTJ)-based memories, this article presents a double data rate magnetic random access memory (DDR-MRAM), which can store information at both clock levels. The proposed memory structure is such that any MTJ type (perpendicular or in-plane) and any switching method can be used as needed. The post-layout simulations based on 40 nm TSMC CMOS technology show that the proposed DDR-MRAM has at least 52% lower write PDP and at least 32% less area-to-maximum input frequency ratio than the conventional MRAMs. Monte–Carlo simulations also confirm the correct and robust operation of the proposed memory in the presence of the inevitable process variation. Moreover, based on the designed DDR-MRAM cell, three architectures are proposed to design $m\times n$ DDR-MRAM arrays. These architectures are designed and optimized for a specific application, including artificial intelligence (AI) hardware accelerators, high-capacity memory banks, and high-speed cache memories. The simulation results of the proposed $m\times n$ DDR-MRAM arrays show that these arrays offer 100% higher data frequency and at least 28% less area-to-maximum input frequency ratio than the conventional MRAM arrays. [ABSTRACT FROM AUTHOR]

We investigated the structural, magneto-electronic, and thermoelectric properties of V2CoZ (Z = Ga, and Ge) Heusler alloys using the ab-initio method. The XA-type structure within the ferrimagnetic phase is more energetically stable than other phases through the chemical stability so the negative value of energy formation that both compounds are favorable and synthesizable experimentally. Both compounds' mechanical properties show anisotropic ductile materials. In addition to their half-metallic ferrimagnetic behavior with an integer total magnetic moment, according to magneto-electronic calculations. Boltzmann's transport theory was also used to investigate the thermoelectric response. Our findings show that these Heusler alloys have a lot of potential for thermo-spintronic devices. [ABSTRACT FROM AUTHOR]

Conventional spin-transfer torque-based magnetoresistive random access memory (STT-MRAM) with CoFeB electrodes has great potential as universal memory. However, state-of-the-art STT-MRAM technology has encountered the issues such as high writing current density and low thermal stability for scaling down to $1\times $ nm. Heusler alloy has been suggested as an alternative to resolve these problems by significantly reducing the Gilbert damping constant while preserving approximately 100% spin polarization. In particular, $L2_{1}$ -ordered Co2FeAl (CFA)-based magnetic tunnel junction (MTJ) exhibits outstanding half-metallicity and perpendicular magnetorcystalline anisotropy characteristics arising from Co(Fe)-O orbital hybridization at the interface. In this work, we investigate the biaxial strain effects of CFA-based MTJ by adjusting in-plane lattice constants from −4% to +4%. Our density functional theory - nonequilibrium Green’s function (DFT-NEGF) calculations present that FeAl-O interfaced MTJ shows a converged tunneling magnetoresistance (TMR) ratio under compressive strain while Co2-O interfaced MTJ shows strain-sensitive TMR ratio under both compressive and tensile strain. The difference in the current-density trends for the two types of MTJs is mainly attributed to the additional state arising from Fe-O bonding. Our results emphasize the careful control of straintronic techniques on CFA-MTJs. [ABSTRACT FROM AUTHOR]

A theoretical investigation of the structural, electronic, magnetic, and magneto-elastic properties is provided for the non-perovskite HoMnO3 in low symmetry. This study has been carried out using density functional theory (DFT + U) with the inclusion of the polarized spin and spin–orbit coupling for both ferromagnetic and antiferromagnetic configurations. The generalized gradient approximation (GGA), the GGA + U, and modified Becke–Johnson (mBJ) approach have been used. The stability of the ground state of this compound in ferromagnetic (FM) and antiferromagnetic (AFM) configurations has been highlighted, confirming the magnetic behavior of HoMnO3. A good agreement has been observed between the internal atomic relaxation calculations and the experimental data. The calculated total magnetic moment of HoMnO3, localized on Ho atom is about ~ 9.6 µB for the ferromagnetic configuration, in good agreement with the available experimental data. On other hand, the GGA and GGA + U (where U ~ 7 eV) approximations have predicted a metallic behavior behavior for the h-HoMnO3, whereas, the implementation of mBJ approach has highlighted a semiconductor feature of the HoMnO3 with spin-polarized band gap about 0.5 eV (FM) and 0.6 eV (AFM). The calculated Bulk modulus has been found to be about 162.23 GPa (FM), and 169.34 GPa (AFM). [ABSTRACT FROM AUTHOR]