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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]

High spin polarization and low resistivity of Fe3O4 at room temperature have been an appealing topic in spintronics with various promising applications. High-quality Fe3O4 thin films are a must to achieve the goals. In this report, Fe3O4 films on different substrates (SiO2/Si(100), MgO(100), and MgO/Ta/SiO2/Si(100)) were fabricated at room temperature with radio-frequency (RF) sputtering and annealed at 450 °C for 2 h. The morphological, structural, and magnetic properties of the deposited samples were characterized with atomic force microscopy, X-ray diffractometry, and vibrating sample magnetometry. The polycrystalline Fe3O4 film grown on MgO/Ta/SiO2/Si(100) presented very interesting morphology and structure characteristics. More importantly, changes in grain size and structure due to the effect of the MgO/Ta buffering layers have a strong impact on saturation magnetization and coercivity of Fe3O4 thin films compared to cases of no or just a single buffering layer.

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]

Exploring magnetic order in nonferromagnetic substances, such as CuO:ZnO, becomes especially attractive when introducing defect states through nonmagnetic ion doping. In this study, we delved into the impact of Yb doping on the structural, morphological, optical, and magnetic properties of CuO:ZnO. The Yb doped CuO:ZnO was prepared with different Yb concentrations (x = 0.00–20 %) via the temperature-assisted co-precipitation method. X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDX), field emission scanning electron microscopy (FE-SEM), high resolution transmission electron microscopy (HR-TEM), X-ray photoelectron spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), UV–Vis spectroscopy, and vibrating sample magnetometer (VSM) were used to investigate the structural, morphological, optical, and magnetic properties of Yb doped CuO:ZnO nanocomposites. The incorporation of Yb in CuO:ZnO nanocomposites leads to a notable shift of the characteristic XRD peaks of CuO and ZnO to lower angles, accompanied by an increase in the lattice parameters. UV–visible absorption spectroscopy shows an overall decrease in the optical band gap energy of ZnO as the Yb defect level increases. FE-SEM studies revealed the transformation of spherical structures into agglomerated non-spherical structures upon the introduction of Yb ions into CuO:ZnO nanocomposites. According to XPS data, the predominant valences of Yb-doped CuO:ZnO nanocomposites are Zn2+, Cu2+, and Yb3+. One noteworthy observation from the XPS results is that, in comparison to the intensity of O L or O ad peaks, the intensity of O V (Oxygen vacancy) defect peak increases when the Yb impurity concentration increases. Magnetic measurements demonstrated a diamagnetic order in pure ZnO, which converts to a ferromagnetic order with the incorporation of Yb defect states. The ferromagnetic properties of the Yb-doped CuO:ZnO nanocomposite can be ascribed to the exchange interaction of Yb3+ ions with defect states (Oxygen Vacancy) in ZnO and CuO. [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]

In this manuscript, structural, opto-electronic, and magnetic properties of pure LaN and binary compounds doped with third-order transition metal ions Mn, Fe, and Co have reported. Here, WIEN2k, spin-polarized plane-wave Density Functional Theory is incorporated into the Full Potential Linearized Augmented Plane Wave formalism. The band gap decrease was observed for every combination of dopants used turns LaN characteristics into a ferrimagnetic material. The magnetization in the transition metal-doped c-LaN compounds is caused by the p-d hybridization of the nitrogen and 3d transition metals. It has been found that Curie temperature Tc of more 747.24, 927.99 and 746.99 has been observed for La0.75Mn0.25N, La0.75Fe0.25N, and La0.75Co0.25N respectively. Mn/Fe/Co co-doped LaN performed best due to its enhanced absorption of visible-infrared and near ultraviolet photonic energies. As a result of the doping, both the dielectric constant and refractive index increased. LaN co-doped with Mn, Fe, and Co showed a static dielectric constant of 44.72 and a refractive index of 6.74. Hence the resulted values with high curie temperature specially for La0.75Fe0.25N suggests that TM doped LaN is a promising material for spintronic applications, especially as spin filter 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]

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.

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]

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.

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.

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]

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]

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]

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]

This work presents methods for addressing undesirable thermal effects induced by the pump beam of an oscillator laser to improve the efficiency of a terahertz (THz) spintronic emitter. We explore two approaches: spatial distribution of pump energy using a 2D lens array and temporal modulation of the pump duty cycle. Optimizing the spatial distribution approximately doubles the THz signal by increasing local heat dissipation, delaying the saturation limit. Similarly, temporal spreading of pump pulses by adjusting the duty cycle allows greater thermal relaxation within the heterostructure, enhancing the overall efficiency of THz wave generation.

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]