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Spintronics is a rapidly developing field in advanced technology. It focuses on manipulating the spin of electrons to achieve high-speed data transfer, handling, and storage in order to enhance its capabilities. We conducted a systematic investigation of the ferromagnetism, electronic, and thermoelectric characteristics of spinel compounds LiFe 2 (O/S) 4. Our analysis for optimization demonstrates that ferromagnetic states exhibit great energy release compared to the antiferromagnetic states, indicating the presence of ferromagnetic behavior in the studied compounds. To evaluate the presence of ferromagnetism above room temperature, we employ the Heisenberg model to calculate the Curie temperature and spin polarization to evaluate the presence of ferromagnetism above room temperature. Additionally, a concise overview of the nature of ferromagnetism, including band structures, density of states, exchange energies and constants, hybridization double exchange model, and crystal-field energy, is provided in this research. The absorption of a shift in magnetic moment from Fe to the Li and O/S sites suggests that the ferromagnetic behavior is primarily due to the spin of electrons. Furthermore, we explore the impact of the thermal parameters on the electro-spin as well as the thermoelectric characteristics for both spin-down and spin-up states, providing insights into the energy-harvesting potential. • Half-metallic ferromagentic spinels LiFe 2 (O/S) 4. • Elastic constant are investigated for structural stability. • Electronic and magnetic properties for spintronic applications. • Magnetic moments are discussed for both compounds. • The electronic and lattice thermal conductivity are calculated for thermoelectric characteristics. [ABSTRACT FROM AUTHOR]

• The formation energy of Fe2+ in the β-Ga 2 O 3 matrix is lower than that of Fe3+, and the system is more stable when the Ga or O vacancies (V Ga or V O) are adjacent to the Fe lattice position. • The β-Ga 31 Fe2+/3+O 47 and β-Ga 30 Fe2+/3+O 48 systems all exhibit ferromagnetism with above-room-temperature Curie temperature. Ga 30 Fe2+/3+O 48 has more spin-polarized O atoms in the same direction. • The magnetism originates from the double-exchange interaction of the coupling and hybridization of the Fe-3d state of Fe3+ and the O-2p state. • Ga 30 Fe3+O 48 system achieves semi-metallization with 100 % hole spin polarization. Induced by the spin-polarized double-exchange interaction between the 3d orbitals of Fe atoms and O-2p orbitals near the O/Ga vacancy complexes, the origin of magnetism in β-Ga 2 O 3 is investigated by using geometry optimization and energy calculation based on the first-principles generalized gradient approximation Hubbard + U method of density-functional theory. The results show that the formation energy of Fe2+ in the β-Ga 2 O 3 matrix is lower than that of Fe3+, and the system is more stable when the Ga or O vacancies (V Ga or V O) are adjacent to the Fe lattice position. It is found that the β-Ga 31 Fe2+/3+O 47 and β-Ga 30 Fe2+/3+O 48 systems all exhibit ferromagnetism with above-room-temperature Curie temperature. β-Ga 30 Fe2+/3+O 48 (i.e., with Fe2+/3+ and V Ga) has more spin-polarized O atoms in the same direction. The magnetism originates from the double-exchange interaction of the coupling and hybridization of the Fe-3d state of Fe3+ and the O-2p state, which increases the magnetic moment of the β-Ga 30 Fe3+O 48 system. This study provides a theoretical reference for designing and preparing new β-Ga 2 O 3 -based dilute magnetic semiconductors and related spintronic and optoelectronic devices. [ABSTRACT FROM AUTHOR]

The magnesium based spinel chalcogenides are outstanding materials for spintronic technology and energy applications. Herein, the modified Becke Johnson potential (TB-mBJ) was employed to investigate the electrical, ferromagnetism, and thermoelectric properties of MgDy 2 (S/Se) 4 spinels comprehensively. The energy emitted during optimization as well as formation energy has both been used to demonstrate the stability of the cubic phase. The density of states, Curie temperature, exchange coupling, and spin polarization are elaborated to address the nature of ferromagnetism. Further, half metallic ferromagnetism is studied in terms of hybridization, exchange energies, and exchange constants. In contrast to the clustering effect of the internal magnetic of Dy atoms in the structure, the lowering of Dy's magnetic moment and its transferring on Mg, and S/Se sites demonstrate that the ferromagnetism is caused by the exchange of electron spin. Furthermore, thermoelectric properties were studied and various thermoelectric parameters such as electrical and thermal conductivities, Seebeck coefficient (S), and power factor (PF) of the examined spinels have been determined. • Above room temperature ferromagnetism, and spintronic applications. • Quantum spin of electrons dominant the charge with multifuctional properties. • Exchange mechanism certifies the ferromagnetism by electron spin instead of magnetic ion clustering. • Half metallic ferromagnetism and 100 % spin polarization. • Large value of electrical conductivity and ultralow low values of thermal conductivity. [ABSTRACT FROM AUTHOR]

Spintronic is the developing technology which probes the properties of quantum devices with spin of electrons which reduce the size and enhance its speed. Therefore, here the role of 5d electrons and thermoelectric characteristics of double perovskites (DPs) K 2 ZCl/Br 6 (Z = Ta, W, Re) elaborated comprehensively by density functional theory (DFT). The Heisenberg model spin polarization density (SP) has been applied to evaluate the Curie temperature (T c) and spin polarization factor. The tolerance factor (t F) and formation energy (ΔH) have been calculated to confirm the stability of structures. Ferromagnetism has been discussed in terms of spin polarization, crystal field energy (Δ CF) and exchange energies (Δ(d), Δ(pd)). The double exchange mechanism, and exchange constants ensure the role of electrons spin in ferromagnetism instead of segregation of transition metal ions. The transferring of magnetic moments of transitions metals to nonmagnetic sites (K, Cl, Br) show the exchange of spin of electrons and integer values of total magnetic moment show 100 % spin polarization. Finally, the transport properties are studied in standings of electrical and thermal conductivities. The large value of Seebeck coefficient and power factor ensure the importance of studied DPs for thermoelectric generators. • Spintronic and energy harvesting applications. • Large value of Curie temperature and high spin polarization. • The ferromagnetism by electron spin instead of magnetic ion clustering. • Half metallic ferromagnetism evidence complete spin polarization. • Ultralow low values of thermal conductivity and Large power factor. [ABSTRACT FROM AUTHOR]

Density of states and band structures reveals 100% spin polarization and half metallic ferromagnetism. [Display omitted] • The Half metallic ferromagnetism, and spintronic applications. • Magnesium ion battertties and energy storage. • The ferromagnetism due to electron spin as an alternative of magnetic ion clustering. • Above room temperarue Curie temperature and 100% spin polarization. • Ultralow low thermal conductivity and Large value of electrical conductivity. The ferromagnetism due to rare earth elements-based spinel chalcogenides has become emerging aspirant for spintronic devices. Therefore, theoretically computed electronic properties of MgTb 2 (S/Se) 4 spinels are analyzed to comprehend the structural, magnetic, and thermoelectric characteristics. Thermodynamic stability is elucidated using the computed enthalpy of formation (ΔH), phonons dispersion band structures. Using structural optimizations, difference in the energy states has revealed the ferromagnetic (FM) state stability. The computed band structures (BS) and density of states (DOS) both depict a half-metallic ferromagnetic state exhibiting a net spin polarization at the Fermi energy level. The underlying ferromagnetic state has been suggested due to carrier mediated indirect RKKY exchange mechanism. The thermoelectric properties are calculated to evaluate their potential for wasted-heat to useful-electricity conversion applications. The small thermal conductivity, and high-power factor exhibited by MgTb 2 S 4 at room temperature suggest it significant for applications in thermoelectric generators. [ABSTRACT FROM AUTHOR]

The structure, electrical transport, and magnetic properties have been systematically studied in superconducting Ti 1− x Mg x O (x = 0, 0.003, 0.02, 0.08, and 0.27) films. It is found that, both the zero resistance and onset superconducting transition temperatures of Ti 1− x Mg x O first increase with increasing the Mg content from x = 0 to x = 0.02, and then decrease with the further increase of x. More interestingly, the Mg-doping simultaneously introduces a ferromagnetic order into this superconducting system, and the ferromagnetism gradually increases with increasing Mg content. According to the first-principles calculations, the non-monotonous Mg doping-dependent superconductivity, carrier density, and disorder strength may be explained as that the Mg atoms first fill the Ti vacancy sites and then substitute the Ti atoms. The calculations also reveal that the ferromagnetism is highly related to the spin polarization of 3 d states of Ti atoms surrounding Mg atoms. The discovery of enhanced superconductivity with coexisting ferromagnetism in Ti 1− x Mg x O films provides an excellent platform to investigate the interaction between superconductivity and ferromagnetism. Image, graphical abstract [ABSTRACT FROM AUTHOR]

The spintronic is an emerging technology which controls the properties of multifactional devices with spin of electrons. In present manuscript, Wien2k and Boltz Trap codes are used to explore electronic, magnetic, and thermoelectric characteristics of Sr 2 CrXO 6 (X = Nb, Mo) double perovskites (DPs). The evaluation of energies released in paramagnetic (PM), antiferromagnetic (AFM), and ferromagnetic (FM) states assure the stability of FM states. Both the negative formation energy and the tolerance factor confirm structural and thermodynamic stability in FM states. The 100 % spin polarization was confirmed by both integer values of magnetic moment (MM) and the spin polarization factor. The values of exchange energy, double exchange model, hybridization of p-d states, and exchange constants are calculated to explore the nature of ferromagnetism and spin functionality. The effect of thermoelectric parameters on spin of electrons and thermoelectric performance are elaborated by thermal to electrical conductivity ratio, Seebeck coefficient and power factor. • High Curie temperature, and spintronic applications. • Spin of electrons overcome the charge with multifuctional properties. • Double exchange mechanism confirms the ferromagnetism by electron spin instead of magnetic ion clustering. • Half metallic ferromagnetism and 100 % spin polarization. • Large value of electrical conductivity and low values of thermal conductivity. [ABSTRACT FROM AUTHOR]

The double perovskites (DPs) have become emerging aspirant for spintronic technology because of their stable, and multifunctional properties. Here in present article, the role 5d-electrons of Ta, W, Re, and Os in ferromagnetism, and thermoelectric behavior has been illustrated briefly. The ideal values of tolerance factor, formation energy and phonons dispersions are reported for structural, thermodynamic, and lattice dynamic stabilities. The higher Curie temperature and spin polarization has been addressed by Heisenberg model and spin density calculations. The ferromagnetism has been explained by the metallic and insulating channels of spin up and spin down configuration through hybridization, exchange energies, and exchange constants. The shifting of magnetic moments from Cr and X sites to Ba, O and interstitial sites ensures the exchange coupling due to spin of electrons rather than clustering. Furthermore, thermoelectric effect on the spin degree of electrons and transport characteristics are calculated by BoltzTraP code. • Above room temperature ferromagnetism. • Spin of electrons dominant the charge. • Electron spin instead of magnetic ion clustering. • Half metallic ferromagnetism evidence 100% spin polarization. • Ultralow low values of thermal conductivity. [ABSTRACT FROM AUTHOR]

The double perovskites have outstanding properties for spintronic devices as they are stable, non-toxic, and accomplish the spin polarization. This article studies the function of 5d-electrons of Ta, W, Re and Os to regulate the magnetic properties of Sr 2 CrXO 6. The tolerance factors and formation energies confirm the stability of the structures and the thermodynamics. The half-metallic ferromagnetic nature is found by analyzing the density of states and band structures described by the double exchange model, exchange energy, and exchange constants. According calculations, ferromagnetism is induced by the electron spin due to hybridization process, magnetic moments, exchange energies, and crystal field energy. The thermoelectric applications are further explored by computing and discussing the thermal and electrical conductivities, and Seebeck coefficients. The power factor has also been elaborated for the performance of studied DPs. • Ferromagnetism at high temperature, and spintronic applications. • Spin of electrons operates the devices with multifuctional properties. • Role of 5d electrons and exchange of energies. • Half metallic ferromagnetism and complete spin polarization. • Ultralow low values of thermal conductivity. [ABSTRACT FROM AUTHOR]

• The intrinsic room-temperature ferromagnetic behavior can be realized and regulated by external strain. • The structural deformation not only regulates the spin polarization feature but also leads to an electronic reconfiguration. • Our findings provide a new insight into designing 2D spintronic devices by strain engineering in hexagonal MIn 2 S 4 monolayers. The electronic occupation at 3d transition metal and crystal symmetry play a critical role in realizing spin polarization, but the weak spin exchange interaction makes it difficult to obtain room-temperature ferromagnetism, especially in two-dimensional (2D) materials. Different from traditional bulk phase with semiconducting feature, the free-standing hexagonal MIn 2 S 4 (M = Fe, Co, Ni, Mn) monolayers are proposed to discuss the strain-dependent magnetic behavior, in which the 3d-orbital hybridization and charge transfer can be regulated by structural deformation to enforce their spin exchange interaction, finally leading to a room-temperature 2D magnetic characteristic. The calculations disclose that the structural deformation not only regulates the spin polarization feature but also leads to an electronic reconfiguration. Our findings provide a new insight into designing 2D spintronic devices by strain engineering in hexagonal MIn 2 S 4 monolayers. [ABSTRACT FROM AUTHOR]

We present our work on the structural, electronic and magnetic properties of monolayer-CdS which was subjected to bi-axial strain and hydrogenation at possible adsorption sites using the first-principles calculations. The results show that both bulk-CdS and monolayer-CdS are non-magnetic direct (Γ − Γ) band-gap semiconductors. By applying a compressive strain up to −10 % the monolayer-CdS remain direct band-gap semiconductor with a maximum band gap value of 2.11 eV. In contrast, a semiconductor to metal transition occurred at 17 % applied tensile strain. Moreover, hydrogenation on all possible adsorption sites induces ferromagnetism and p -type conductivity in monolayer-CdS. Among all possible adsorption sites, H added on the Cd-top site is the most probable site showing strong ferromagnetism and half-metallicity. The strong ferromagnetism means 100 % spin polarization is retained up to applied bi-axial strain of −5 % to +15 %. Also, half-metallicity is robust under the bi-axial strain in the range of −4 % to +2 %. To determine the strength of the exchange-coupling parameter, the FM (ferromagnetic) and AFM (anti-ferromagnetic) coupling between added atoms was investigated under the bi-axial strain of −5 % to + 5 %. Our findings show that H added on the Cd-top site makes it ferromagnetic and half-metallic above room temperature. The maximum Curie temperature T c = 651.41 K is achieved at a strain of ɛ = −2 % of ferromagnetic state. This high Curie temperature has not been achieved for any 2D material to-date. The present work provides a route to harness the ferromagnetism and thermal stability of 2D monolayer-CdS for electronic and spintronic applications. [ABSTRACT FROM AUTHOR]

The optimized plots of MgBeO 3 , CaBeO 3 , SrBeO 3 and BaBeO 3 in FM state by GGA approximation (b) Crystal Structure designed by Xcrysden taking 2 × 1 × 1 unit cell. • The structural, mechanical and thermodynamic stability ofperovskites. • Room temperature ferromagnetism. • Half metallic ferromagnets with hundred percent spin polarization. • Exchange mechanism exceed the exchange energy than crystal field energy. • The cause of ferromagnetism is spin of electron rather than clustering effect. We investigate the Half-metallic ferromagnetism and optical behaviors of XBeO 3 (X = Mg, Ca, Sr and Ba) using full-potential linearized augmented plane-wave method. The structural and thermodynamic stabilities are elucidated in terms of the calculated tolerance factor and enthalpy of formation, respectively. The room temperature (RT) ferromagnetism is shown by computing the Curie temperature and spin polarization. The strong hybridization between p -states of alkaline earth metals and 2 p -states of oxygen near the Fermi level results total magnetic moment of 2μ B. The ferromagnetism occurs due to holes those result in the exchange interactions between the p-states of alkaline earth metals and oxygen. The potential optical applications are also suggested by computing the dielectric constant and refraction. [ABSTRACT FROM AUTHOR]

A detailed experimental and theoretical investigations on the origin of room temperature ferromagnetism in Fe doped CdS diluted magnetic semiconductor is reported in the present study. X-ray diffraction results reveal the cubic zinc blende CdS structure with an average crystallite size of 2 nm–3 nm which is in concurrence with the Transmission electron microscopy results. UV–visible spectroscopy depict the enhancement of optical band gap of Fe doped CdS nanoparticles compared to the bulk CdS as a result of the quantum confinement effect. Photoluminescence spectra revealed the presence of Cd2+ and S2− defect states in the nanoparticles in addition to the fluorescence quenching effect. FTIR results demonstrate the stretching vibrations of Cd S bond. Magnetic study confirms the existence of room temperature ferromagnetic ordering in the nanoparticles for the lower concentration of Fe, as a result of spin polarization induced by the Fe atoms to the nearest neighboring S atoms. At higher concentration of Fe, the enhanced antiferromagnetic interaction between short range Fe ions suppresses the ferromagnetic ordering. Theoretical calculations demonstrate the half metallic nature of Fe doped CdS system with strong p-d hybridization between the Fe-d states and the S-p states which results the room temperature ferromagnetism. • DFT calculations are performed to investigate the ferromagnetic ordering in the Fe doped CdS nanoparticles. • Fe doped CdS system shows half metallic properties. • The ferromagnetic ordering is due to p-d exchange interaction between the localized d spins of the Fe ions and the free delocalized carriers. • p-d hybridization between the d states of Fe and the p states of S are observed in the Fe doped CdS system. [ABSTRACT FROM AUTHOR]

Abstract By applying the slave-boson mean-field approximation to the highly correlated quantum dots (QDs), we investigate the spin polarized transport properties through serial two QDs coupled with Majorana bound states (MBSs) sandwiched between two ferromagnetic (FM) leads. We demonstrate the linear conductance and transmission properties which is dependent on the QD-MBS coupling strength and the spin polarization strength. We further discuss the exact up-and down-spin transmission properties in the parallel and anti-parallel configurations. We suggest that such a theoretical model can be used to study the physical phenomenon related to the spin manipulation transport in the hybrid Majorana quantum-dot systems. Highlights • We demonstrate the linear conductance and transmission properties depending on the QD-MBS coupling and the spin polarization. • The linear conductance increases with the QD-MBS coupling and the up-spin electrons dominates that of down-spin electrons. • The up-spin (down-spin) transmission decreases (increases) with the increasing spin polarization strength under parallel configuration. • The up-spin transmission is always identical with the down-spin under anti-parallel configuration. • The obtained results can be used to the spin manipulation transport in the hybrid Majorana quantum-dot systems. [ABSTRACT FROM AUTHOR]

Highlights • Interface termination of FeRh films on MgO has a tremendous effect on the magnetic-phase order and magnetic anisotropy. • The presence of Rh layer at the interface next to MgO as well as vacuum leads to a very robust interfacial ferromagnetism and large magnetic anisotropy of about 2 meV, which is an order of magnitude greater than those for the Fe-terminated FeRh/MgO. • This large anisotropy is attributed to the interplay of the spin-polarized Rh d xy and d x 2 - y 2 orbital states with large spin-orbit coupling at the interface. Abstract Employing first-principles calculations we reveal the strong interface termination dependences of the magnetic order and perpendicular magnetic anisotropy (PMA) in FeRh films on MgO(0 0 1). While the magnetic ground state of the Fe-terminated FeRh(0 0 1) is an antiferromagnetic, the Rh-termination favors ferromagnetism within the underlying FeRh layers. This ferromagnetism can persist even at the interface with MgO, which in turn leads to a few times enhancement of PMA compared with the Fe-interface in FeRh/MgO(0 0 1). The underlying mechanism for this large PMA is an interplay between the spin-polarized Rh d xy and d x 2 - y 2 orbital states with large spin-orbit coupling at the interface. These results unveil a crucial role of the interface termination on magnetism of FeRh in antiferromagnet spintronics. [ABSTRACT FROM AUTHOR]

Abstract The electronic structures and magnetic properties of 6H-SiC doped with N, C vacancies (V C), Si vacancies (V Si) and Al are studied by first principles calculations. The results indicate that the N substituting C in 6H-SiC cannot order magnetism but V Si can introduce magnetic moments effectively. Ferromagnetism coupling is obtained in (N, 2 V Si)-codoped 6H-SiC. The ferromagnetism can be mainly attributed to the interactions between the 2 p orbitals of C atoms around Si vacancies. More interestingly, substituting Si with Al can enhance the ferromagnetic states in 6H-SiC in neutral states. We also studied the effect of charge on magnetic properties and provide an effective method of tuning magnetism in 6H-SiC. Highlights • The doping with N Si , V Si and (N C , V Si) can induce ferromagnetism in 6H-SiC crystal. • Ferromagnetism can be enhanced by Al substituting and charge. • The spin polarization is proposed as the origin of ferromagnetism. [ABSTRACT FROM AUTHOR]

Abstract Molecular bridges covalently bonded to two ferromagnetic electrodes can transform ferromagnetic materials and produce intriguing spin transport characteristics. Previously, we theoretically and experimentally studied the impact of paramagnetic molecules on the magnetic properties of the magnetic tunnel junctions (Tyagi et al. Nanotechnology, Vol.26, p.305602, 2015). In this follow up paper we have investigated the impact of previously demonstrated molecule induced strong coupling on the spin transport. To study molecular coupling effect experimentally we attached paramagnetic molecules between two ferromagnetic electrodes of a magnetic tunnel junction along the exposed side edges. The strong molecule coupling between two ferromagnetic electrodes caused the drastic changes in transport properties of the magnetic tunnel junction testbed. Molecular transport channels along the tunnel junction edges decreased the tunneling current as compared to the leakage current of the bare tunnel junction at room temperature. The current magnitude on the paramagnetic molecule treated magnetic tunnel junction tended to settle in the suppressed state at room temperature. Graphical abstract Image 1 Highlights • Covalently bonded molecules created experimentally-observed strong antiferromagnetic coupling between ferromagnets of MTJ. • Upto ~ 7 orders of current reduction below leakage current of MTJ occurred on MTJMSD due to molecular bridges at RT. • In the transient state MTJ+molecules (aka MTJMSD) showed irreproducible magnetoresistance change by >1000 folds at RT. • In the transient state forcing current through MTJMSD showed irreproducible resistance change by >1000 folds at RT. • MTJMSD approach may allow mass production of molecular quantum properties based future computing and memory devices. [ABSTRACT FROM AUTHOR]

The density functional theory (DFT) studies are made to calculate the electronic, magnetic, and transport characteristics of potassium lanthanide KXO2 (X = Pr, Nd, and Pm) oxides have been studied by using the WIEN2K code. Perdew Burke Ernzerhof-Generalized Gradient approximation (PBE-GGA) is used for the exchange-correlation energy of the crystal structures in the hexagonal phase. However, the volume-optimized graphs depict that these compounds are energetically stable in the ferromagnetic state. Moreover, the studies of the spin-up channels of the band structure and density of states (DOS) reveal their metallic behavior whereas semiconductor nature has been noticed through spin-channels. Therefore, studied materials have half metallicity nature with 100% spin polarization at the Fermi level (EF). Total and partial magnetic moments of KXO2 (X = Pr, Nd, and Pm) and individual atoms exist due to unpaired 4f electronic states of the lanthanide ions, present at the EF. The energy difference between anti-ferromagnetism and ferromagnetism versus the volume optimization curve gives the curie temperature (Tc). The volume optimization curves show a flat region where both magnetic states have similar energies. This means the material can exist at the equilibrium volume in either state. Finally, thermoelectric properties are calculated by the BoltzTraP code. Our results unveil that these potassium-based lanthanide oxides are potential materials for devising spintronics devices and lifting future practical applications. • Studied materials have half metallicity nature with 100% spin polarization at E F. • Total and partial magnetic moments of KXO 2 and individual atoms exist due to unpaired 4 f states of La. • Energy difference between anti-ferromagnetism and ferromagnetism energy vs volume optimization curve gives value of T C. • The figure of merit is higher for KPmO2, KNdO2 as compared to KPrO2. [ABSTRACT FROM AUTHOR]

Searching experimental feasible two-dimensional (2D) ferromagnetic crystals with room-temperature magnetic order and high spin-polarization is one key for the development of next-generation spintronic devices. Inspired by the recent experimental achievement for the synthesis of Janus MoSSe monolayer with out-of-plane symmetry, here, by ab initio calculation, we demonstrate this feasibility with the discovery of intrinsic 2D ferromagnetic Janus TMDs monolayer (TMXX′, TM = V, Cr and Mn; X, X′ = S, Se and Te, X ≠ X′) with large spin-polarization and high Curie temperature. Particularly, the MnSSe monolayer show half-metal with 100% spin polarization and wide half-metallic gap. A Curie temperature as high as 400 K has been found for VSSe materials. The formation energy calculation for Janus TMDs can be comparable with the TMDs monolayer. The dynamical stability for these 2D crystals also have been confirmed by phonon spectrum calculation. Our study presents a new class of 2D magnetic materials for future spintronics and valleytronics. [ABSTRACT FROM AUTHOR]

Effect of Cr doping on the magnetic structure and electronic properties of Fe 2 VSi has been investigated by experimental measurement and first-principles calculations. In Fe 2 V 1-x Cr x Si, ferromagnetism can be stabilized with 10% Cr substitution. The Curie temperature T C increases rapidly with increasing Cr content and reaches 365K when x = 0.4. The saturation magnetization M s also increases with increasing Cr content. A small amount of A15 secondary phase is observed with increasing Cr content at x = 0.4, indicating that the solid solubility of Cr in Fe 2 VSi has been reached. In Fe 2 V 1-x Cr x Si, high spin polarization ratio is predicted when x ≥ 0.25, and half-metallic character is observed when x = 0.5, 0.75 and 1.0. The calculated total spin moment M t also increases with increasing x. When x is larger than 0.2/0.25, the experimental/theoretical total moment gets close to the Slater-Pauling curve of M = Z - 24 for half-metallic Heusler alloys. All this makes Fe 2 V 1-x Cr x Si promising candidates for spintronic applications. [ABSTRACT FROM AUTHOR]

Aim of this study is to investigate spin transportation in double quantum ring (DQR). We developed an array of DQR to measure the transmission coefficient and analyze the spin transportation through this system in the presence of Rashba spin-orbit interaction (RSOI) and magnetic flux estimated using S-matrix method. In this article, we compute the spin transport and spin-current characteristics numerically as functions of electron energy, angles between the leads, coupling constant of the leads, RSOI, and magnetic flux. Our results suggest that, for typical values of the magnetic flux ( ϕ / ϕ 0 ) and Rashba constant ( α R ), such system can demonstrates many spintronic properties. It is possible to design a new geometry of DQR by incoming electrons polarization in a way to optimize the system to work as a spin-filtering and spin-inverting nano-device with very high efficiency. The results prove that the spin current will strongly modulate with an increase in the magnetic flux and Rashba constant. Moreover it is shown that, when the lead coupling is weak, the perfect spin-inverter does not occur. [ABSTRACT FROM AUTHOR]

The possibilities of ferromagnetism induced by nonmagnetic dopants (Cu, Zn) in double perovskite S r 2 A l T a O 6 at B sites are investigated by density functional theory. Calculations reveal that substitutions at Ta-site tend to form high spin electronic configurations and could induce ferromagnetism which can be attributed to the hole-mediated p - d hybridization between Cu (or Zn) e g states and the neighboring O 2p states. The dopants preferably substitute at Al-site and adopt low spin electronic structures. Due to the smaller hole concentration and weaker covalent intensity, S r 2 A l T a O 6 with dopants at Al-site exhibits p -type metallic semiconductors without spin polarization. [ABSTRACT FROM AUTHOR]

Recently, Alkahtani et al. [1] studied the structural, electronic and optical properties of pure ZnO and Er-doped ZnO using generalized gradient approximation plus modified Becke-Johnson exchange potential. They doped erbium (Er) atom to ZnO zinc-blende structure. They did not perform spin polarized calculations, so their obtained electronic and optical properties are wrong. Also, the intra-band transition has not been considered in the their optical investigations. The correct form of these properties is presented and discussed in this paper. [ABSTRACT FROM AUTHOR]

First-principles calculations, were carried out to study the structural stability of the cubic [ (F m 3 ‾ m) , (F 4 ‾ 3 m) ] and tetragonal [ (I 4 / m m m) , (I 4 ‾ m 2) ] phases, of R u 2 V Z (S i ; G e) full Heusler compounds; where Energy of formation, elastic, Mechanical, phonon and thermodynamic properties and electronic density of states were determined. Through our results, all ferromagnetic phases exhibit a total magnetic moment of 1 μ B for both R u 2 V S i and R u 2 V G e compounds, except the tetragonal (I 4 ‾ m 2) phase that manifest a zero ( 0 μ B) total magnetic moment.Further, the antiferromagnetic state of the cubic phase F m 3 ‾ m R u 2 V Z (S i ; G e) was found energetically more favorable than the ferromagnetic one.The analysis of the calculated elastic and dynamic properties, revealed that only the regular cubic phase (F m 3 ‾ m) of the R u 2 V S i and the regular tetragonal phase (I 4 / m m m) of the R u 2 V G e are the most stable among the considered phases. The calculated electronic density of states for the ferromagnetic stable phases, confirm the existence of a half-metal character with high spin polarization (P n) of: ∼ 91 % and ∼ 100 % for the R u 2 V S i and R u 2 V G e respectively. • In This article applied the Full full-potential linearized augmented-plane-wave method (FP-LAPW) to the determination of the structural, dynamic mechanical and electronic properties of the two full Heusler compounds R u 2 V S i and R u 2 V G e. • The antiferromagnetic state for the cubic (F m 3 ‾ m) R u 2 V Z (S i ; G e) compounds was found more favorable than the ferromagnetic one. • The analysis of the calculated elastic and dynamic properties, show that only the regular cubic phase (F m 3 ‾ m)) of the R u 2 V S i and the regular tetragonal phase (I 4 / m m m) of the R u 2 V G e are the most stable among the considered phases. • The electronic density of states for the ferromagnetic stable phases, confirm the half-metal character with high spin polarization for the R u 2 V S i and R u 2 V G e respectively. [ABSTRACT FROM AUTHOR]

• The monovacancies (MVs) in Bi monolayer can lead to a transformation from semiconductor to metallicity. • A particular defect configuration can give rise to a spin polarization and room-temperature ferromagnetism. • The physical property difference in Bi monolayer is strongly dependent on defect types. Bismuth (Bi) monolayers have attracted much attention due to their intriguing physical and chemical applications, which are strongly related to the existence of topological defects. However, the intrinsic correlation between the defect types and particular electronic structures of Bi monolayers still needs to be understood. Herein, we intentionally implanted various typical topological defects into Bi monolayers to reveal the differences in the electronic structure, in which the monovacancies (MVs) can lead to a transformation from a semiconductor to a metal. More interestingly, a particular defect configuration can give rise to a spin polarization and room-temperature ferromagnetism, demonstrating the spintronic applications. This work reveals that the physical property differences of Bi monolayers are strongly dependent on their defect types. The topological defects can be intentionally implanted into Bi monolayer to achieve the transformation from semiconductor to metallicity, or a spin polarization and room-temperature ferromagnetism as well. [Display omitted] [ABSTRACT FROM AUTHOR]

Ferromagnetism in half-metallic two-dimensional material can lead to unique spintronics application. In this work, Cr-doped single-layer graphdiyne is predicted to be two-dimensional ferromagnetic semiconductor, and Mn-doped graphdiyne is predicted to be ferromagnetic conductor using first-principle calculations. Cr and Mn adatoms could be stabilized on the corner sites of graphdiyne sheet due to high migration barriers. The currents through Cr- and Mn-doped graphdiyne possess spin polarization feature. For Cr-doped graphdiyne system, the transmission polarization is up to 100% and could be controlled by the gate voltage. Cr-/Mn-doped graphdiyne with spin-polarized semiconductor/conductor properties could be promising material for combined usage in spintronics application. [ABSTRACT FROM AUTHOR]

In an asymmetric two-dimensional electron gas system, the Rashba effective field arises due to the intrinsic electric field. Even without ferromagnetism, the Rashba spin splitting acts as a source of spin polarization and affects the transport property of the two-dimensional electron channel. In this Rashba channel, the magnetoresistance is determined by the vector alignment between the applied field and the bias current. In addition, the channel resistance for the parallel alignment between the applied field and the Rashba field is much smaller than that for the antiparallel alignment between them, which surprisingly agrees with the spin polarization induced by the Edelstein effect. This anisotropic magnetoresistance also allows us to estimate the spin polarization in a two-dimensional quantum well channel. [ABSTRACT FROM AUTHOR]

In this work, we study the transport properties of Dirac fermions through the ferromagnetic silicene which is sandwiched between the Graphene leads (G/FS/G). Spin/valley conductance, spin/valley polarization, and also Fano factor are theoretically calculated using the Landauer-Buttiker formula. We find that the fully valley and spin polarized currents through the G/FS/G junction can be obtained by increasing the electric field strength and the length of ferromagnetic silicene region. Moreover, the valley polarization can be tuned from negative to positive values by changing the electric field. We find that the Fano factor also changes with the spin and valley polarization. Our findings of high controllability of the spin and valley transport in such a G/FS/G junction the potential of this junction for spin-valleytronics applications. [ABSTRACT FROM AUTHOR]

Half-metallic magnets with complete (100%) spin polarization have attracted growing interest due to the potential in spintronic applications. In this paper, we use the first-principles calculations to explain the seeming contradiction between the recent experimental ferromagnetism (Demper et al., 2012 [22]) and the previous theoretical antiferromagnetic ground state for half-metallic zinc-blende CrS, and the experimental ferromagnetism of zinc-blende CrS arises from the substrate effect. We also show that both Cr- and S-terminated (001) surfaces of CrS preserve the bulk half-metallicity. The calculated surface energy indicates that the S-terminated (001) surface is more stable than the Cr-terminated (001) surface within the whole effective Cr chemical potentials, and thus the S-terminated (001) surface is more likely than the Cr-terminated (001) surface when the CrS thin films are grown on ZnSe substrate. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fe and Ni multilayer epitaxy is realized on oxygen-passivated Fe(0 0 1). • Oxygen floats on the surface and affects the magnetic response of the system. • The spin polarization of the photoemission signal is quenched upon Ni growth. • A single Fe layer abruptly restores the polarization signal. • According to simulations, the spectral polarization follows surface magnetization. We investigated the magnetic behaviour of an Fe overlayer on a Ni buffer layer (Fe/Ni multilayer system) grown on top of the Fe- p (1 × 1)O surface, with a particular focus on the modifications observed in the spin-resolved electronic structure and the role of oxygen, introduced in the system in a well-defined amount at the substrate preparation stage. The structural properties are investigated by means of low energy electron diffraction, that confirms the formation of an epitaxial system featuring a metastable surface lattice. Spin-resolved photoemission spectroscopy testifies a strong decrease of the spectral spin polarization for increasing thickness of the Ni buffer layer, reaching a minimum from a nominal thickness of 6 Ni atomic layers. Surprisingly, the growth of a single Fe overlayer is sufficient to restore most of the original polarization signal, thus creating an ultrathin bcc Fe film seemingly decoupled from the substrate. Ab initio calculations track the modifications of the magnetic moments of the surface layers that quench upon Ni deposition and restore with additional Fe growth. Spin-resolved inverse photoemission highlights a notable reduction of the density of majority states just above the Fermi level, possibly influencing the magnetic response of the system. [ABSTRACT FROM AUTHOR]

We use nonequilibrium Green function to analyze the nonequilibrium spin-polarized thermal transport through the ferromagnetic–quantum dot–metal system, in which a quantum dot (QD) is coupled to the ferromagnetic and metal electrodes with the voltage bias and the temperature shift. The differential thermoelectric conductance L ( θ ) is always zero and has no relation with the temperature shift when ε is equal to the Fermi level. The positive and negative values of L ( θ ) manifest the thermoelectric characteristic of electron-like (or hole-like) carrier when the temperature shift is nonzero. The electrostatic potential U becomes spin-dependent, and makes the dot level renormalization when the ferromagnetic–quantum dot–metal system is driven by the voltage bias and the temperature shift. We define that the spin polarization of the currents between the spin current I s and the electric current I c is denoted as I s / I c . The spin polarization I s / I c shows novel and unique physical phenomenon when the voltage bias and the temperature shift are changed in the nonequilibrium state. Another interesting phenomenon is that we can obtain the pure spin current and a zero point of the thermocurrent I t h by adjusting the voltage bias and the temperature shift. [ABSTRACT FROM AUTHOR]

We investigate the electronic structures and magnetic properties of RbSe and CsTe compounds in CsCl, RS and ZB structures by using density functional theory calculation. It is shown that these two compounds exhibit half-metallic ferromagnetism with an integer magnetic moment of 1.00 μ B per formula unit in all the three structures. Total energy calculations indicate the CsCl phase is more stable than the other two phases. We investigate these two compounds with CsCl structure in detail. The ferromagnetism results mainly from the spin-polarization of p states of anion Se (Te) for the two compounds. [ABSTRACT FROM AUTHOR]

We have studied the origin of the magnetism induced by a neutral cation vacancy in rocksalt ScN using ab - initio calculations based on spin density functional theory. Our results showed that Sc vacancy induces a total local magnetic moment of 0.50 μ B . The main contributors to this induced magnetism are the 2 p orbitals of nearest nitrogen atoms surrounding the vacancy. The spin polarization energy (defined as the energy difference between the spin polarized and non-polarized states) is well above the room-temperature energy. Furthermore, we have investigated the effect of an external strain on the induced magnetism. Our calculations showed that applying an external strain leads to a decrease of the stability of the magnetic state. Moreover, calculations of the magnetic interactions showed that the most stable configuration corresponds to the fifth nearest neighbor distance with a ferromagnetic state. Finally, using thermodynamic considerations, we demonstrated that the minimum defect concentration to achieve magnetic percolation cannot be reached at equilibrium conditions. However, we found that by applying an external strain, we could reduce the formation energy of the defect, achieving therefore the magnetic percolation. [ABSTRACT FROM AUTHOR]

We study the possibility to control the spin polarization and spin-dependent transport in a graphene sheet by considering a ferromagnetic layer in the presence of the Rashba spin–orbit interaction. Studying the scattering problem with the help of the Green function (which was found explicitly), we obtained simple analytical expressions for the spin dependent transmission probability. Using the small exchange parameter and Rashba coupling constant, we can obtain any degree of spin polarization, but in the case of a small interaction region, only for slow electrons. [ABSTRACT FROM AUTHOR]

Magnetic properties of Ga vacancies V Ga and vacancy pairs in GaN are analyzed by employing the Generalized Gradient Approximation with the +U corrections. Strong spin polarization stabilizes high spin configurations of V Ga , and leads to its negative- U eff character. Both features are reflected in the magnetic properties of vacancies pairs. Because of electron transfer between two vacancies induced by negative- U eff , both vacancies can be in different charge and spin states, and thus the spin ground states of a pair can be ferrimagnetic rather than ferro- or antiferromagnetic. Magnetic coupling of V Ga – V Ga pairs as a function of separation between the defects, their relative orientation, and of the charge state, was calculated. The strength of magnetic coupling is reduced by the U-induced localization of the wave functions. The obtained results show that gallium vacancies can lead to the observed ferromagnetism in irradiated GaN samples. [ABSTRACT FROM AUTHOR]

The tunneling conductance spectra of a ferromagnetic semimetal/metal junction, where there were electrons and holes with the same spin directions as the essential conducting particle, was theoretically studied based on a scattering approach in a ballistic regime. The main area of interest was to perform a high spin polarization by considering the effect of the interfacial scattering at the interface that was composed of normal and spin-flip scattering, the particle effective mass mismatch on the reflection and transmission probabilities, and spin polarization of conductance. It was found that the spin polarization of conductance decreased with increasing spin-flip scattering. Interestingly, the normal scattering can cause the spin polarization of the conductance to reach a maximum value in the presence of both kinds of scattering. When the particle effective mass mismatch was considered, the spin polarization of conductance was large when the electron effective mass in the valence band was smaller than that in the conduction band. However, in this calculation, the results of a ferromagnetic semimetal/metal junction behaved similarly to those of a ferromagnetic metal/metal junction. [ABSTRACT FROM AUTHOR]

We study ballistic electron transport through single or double barriers on monolayer MoS 2 , of width d , in the presence of a ferromagnetic field M or an antiferromagnetic field F . The total conductance g c , its spin-up and spin-down components, and the polarization oscillate with d or the distance b between two barriers. The corresponding oscillation periods are different. The conductance g c versus M decreases in a fluctuating manner with a steep decline at certain value of M . As a function of M the spin polarization P s oscillates before it becomes 100% while the valley polarization P v oscillates and steadily increases. [ABSTRACT FROM AUTHOR]

Objective : Half-metallic ferromagnetism plays a major role in high-performance spintronic applications due to its 100% spin-polarization. So, it is very necessary to search better half-metallic ferromagnets with large magnetic moment and being compatible with current semiconductor technology. Methods : We study cubic Eu 4 O 3 N on the basis of state-of-the-art first-principles calculations by using generalized gradient approximation plus U method. Results : It is found that the Eu 4 O 3 N is a half-metallic ferromagnet with a half-metallic gap of 376 meV and the large Eu ion magnetic moment up to about 7 μ B . The structural and ferromagnetic stability are proved by mechanical stability criterion and magnetic energy differences, respectively. The half-metallic properties are also stable against the isotropic strain, volume-conservative tetragonal strain and rhombohedral distortion. For the choice of U between 4 and 8 eV, the Eu 4 O 3 N still is half-metallic ferromagnet. Conclusion : This provides a new idea for searching new half-metallic ferromagnetism by f electrons. Practical implications : If the Eu 4 O 3 N was experimentally synthesized with half-metallic properties, it should be used to design high-performance spintronic devices. [ABSTRACT FROM AUTHOR]

We calculate the spatially resolved tunnelling conductance of topological superconductors (TSCs) based on ferromagnetic chains, measured by means of spin-polarised scanning tunnelling microscopy (SPSTM). Our analysis reveals novel signatures of MFs arising from the interplay of their strongly anisotropic spin-polarisation and the magnetisation content of the tip. We focus on the deep Yu–Shiba–Rusinov (YSR) limit where only YSR bound states localised in the vicinity of the adatoms govern the low-energy as also the topological properties of the system. Under these conditions, we investigate the occurrence of zero/finite bias peaks (ZBPs/FBPs) for a single or two coupled TSC chains forming a Josephson junction. Each TSC can host up to two Majorana fermions (MFs) per edge if chiral symmetry is preserved. Here we retrieve the conductance for all the accessible configurations of the MF number of each chain. Our results illustrate innovative spin-polarisation-sensitive experimental routes for arresting the MFs by either restoring or splitting the ZBP in a predictable fashion via: (i) weakly breaking chiral symmetry, e.g. by the SPSTM tip itself or by an external Zeeman field and (ii) tuning the superconducting phase difference of the TSCs, which is encoded in the 4 π -Josephson coupling of neighbouring MFs. [ABSTRACT FROM AUTHOR]

The properties of PuN (0 0 1) surface have been investigated using all-electron full-potential linearized augmented plane wave plus local orbitals basis (FP-LAPW+lo) method at both scalar- and fully- relativistic levels, with and without spin-polarization. The ground state of PuN (0 0 1) surface is found to be ferromagnetic with spin–orbit coupling (FM + SO). At the ground state, the semi-infinite surface energy and average work function for PuN (0 0 1) surface are predicted to be 1.12 J/m 2 and 2.62 eV, respectively. At three layers of formula units and beyond, the PuN (0 0 1) surface properties including total energies per N -formula unit, surface energy, work function and magnetic moment converge, indicating that a 3-layer slab can be used to model PuN (0 0 1) surface to a good approximation. The localization of the 5 f electron states is pronounced at the top surface layer while bulk-like behavior is exhibited at the second and deeper layers. [ABSTRACT FROM AUTHOR]

In search of d 0 magnetism, the magnetic behavior of SnO 2 with cation substitution from group1A (Li, Na, K) and group 2A (Be, Mg, Ca) elements has been systematically studied using Density Functional Theory (DFT). While an impurity from group 1A elements switches on ferromagnetism at a lower concentration itself, sufficient hole density is required for a group 2A impurity to create a spontaneous spin polarized ground state, a finding that has not been reported in earlier investigations. Our DFT results predict for the first time that impurities from group 2A (Mg, Ca) in SnO 2 can promote room temperature ferromagnetism. Further, the emergence of ferromagnetism due to doping from group 1A elements, which injects three holes per defect, has been mapped successfully onto a modified Hubbard model from the literature. Doping of a single Na atom in the supercell (concentration 6.25 at%) makes the system ferromagnetic, with a magnetic moment close to 3.0 μ B per defect, and a Curie temperature of 815 K, obtained in the mean field approximation. This agrees closely with a model prediction of 750 K. Finally, the triggering of ferromagnetism by an impurity atom from group 2A, which adds two holes per defect in the system, implies that the prescription of three holes per defect given in the literature is not a necessary criterion for hole induced ferromagnetism. Rather, the analysis of the density of states and ferromagnetic coupling indicate that the system needs a critical hole concentration to activate ferromagnetism, by pushing the Fermi level inside the valence band in order to satisfy the Stoner criterion. [ABSTRACT FROM AUTHOR]

Ferromagnetic metallic inverse-perovskite (Eu 3 O)In is studied using hybrid functional theory (HF) in the frame work DFT. The calculated structural parameters and geometries of the material are calculated by different exchange correlation potentials and found that HF results are closed to the experiments. Electronic charge density explains the bond nature and polarization. The spin polarized electronic band profiles and density of states reveal the metallic nature of the compound. The Eu f-state splitting show that the valance bands are dominated mainly by f-[a 2 ], f-[x(T 1 )], f-[y(T 1 )] and f-[z(T 1 )] states. The ground state magnetic phase of the compound is optimized. The optimum energy and magnetic susceptibility confirm the ferromagnetic nature of the compound. On the basis of different properties presented it is predicted that this compound is magnetoresistive material. [ABSTRACT FROM AUTHOR]

Recently, p -type conduction of InN doped by alkaline earth was reported in experiments. However, the magnetic property of the doped systems has not been studied. We systematically investigate the magnetic property of alkaline-earth doped InN by density-functional theory. Our results reveal that the ground state of the doped system transits from nonmagnetic state to spin-polarized state, and the holes introduced into the valence band become more localized as the defect ranges from Be to Ba. As a result, strong half-metallic ferromagnetism emerges for Sr- or Ba-doped InN. Our calculations reveal that the formation energy of defect is much lower for nitrogen-rich condition, under which the doped system can be favorably synthesized. [ABSTRACT FROM AUTHOR]

A new type of nano-junctions based on Zigzag graphene nanoribbons (ZGNRs) has been proposed and investigated by first-principles calculations. The results show that large spin polarization of currents would be achieved when the junctions adopted the configuration that two ZGNR leads coupled each other along one edge. By virtue of spatial separation of the two spin edge states, only one spin channel is opened in those junctions at certain energy range, and spin polarized currents will be produced under a low bias. No more efforts are required to change ZGNR from the antiferromagnetic (AFM) ground states to the ferromagnetic (FM) states. Specially, this feature is stable, by changing the width of ZGNRs, modifying the edge morphology, and varying dihedral angle between two ZGNRs, spin polarization of currents are still observed. Our findings indicate that this approach is simple and efficient for spintronics design. [ABSTRACT FROM AUTHOR]

The structural, elastic, electronic and magnetic properties of the diluted magnetic semiconductors Mn x Ca 1− x S in the rock-salt phase have been investigated using first-principles calculations with both LDA and LDA + U functional. Features such as lattice constant, bulk modulus, elastic constants, spin-polarized band structure, total and local densities of states have been computed. We predict the values of the exchange constants and the band edge spin splitting of the valence and conduction bands. The hybridization between S-3p and Mn-3d produces small local magnetic moment on the nonmagnetic Ca and S sites. The ferromagnetism is induced due to the exchange splitting of S-3p and Mn-3d hybridized bands. The total magnetic moment per Mn of Mn x Ca 1− x S is 4.4μ B and 4.5μ B for LDA and LDA + U functional and is independent of the Mn concentration. The unfilled Mn-3d levels reduce the local magnetic moment of Mn from its free space charge value of 5μ B –4.4μ B and4.5μ B for LDA and LDA + U functional due to 3p–3d hybridization. [ABSTRACT FROM AUTHOR]

Cr/C composite films with 7.9 and 8.5 at% Cr contents were fabricated by facing-target magnetron sputtering. Cr nanoparticles are embedded in amorphous carbon matrix, and Cr atoms bond with C atoms at the interface. The Cr/C films were found to exhibit ferromagnetism in the temperature range of 2-300 K, which is probably induced by uncompensated spins at the surface of Cr nanoparticles. Spin-dependent magnetoresistance (up to ?19.5% at 90 kOe and 2 K) was observed in the Cr/C films. The negative MR originates from the alignment of the uncompensated spins at the interface between nanoparticles and matrix. The spin polarization which comes from the interfacial p-d hybridization was calculated to be 21% and 17% in the Cr/C films with 7.9% and 8.5% Cr, respectively. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials with intrinsic ferromagnetism, a sizable magnetic anisotropy energy (MAE) and large spin polarization are desirable for realizing the practical spintronic applications. Base on first-principles calculations, the stability, electronic and magnetic properties of monolayer CrOBr are systematically investigated. Monolayer CrOBr is ferromagnetic semiconductor with a band gap of 1.547 eV, it possesses in-plane magnetic anisotropy with a value of −0.017 meV/formula unit (f.u.). The band gap of monolayer CrOBr can be regulated in the range of 1.547-1.145 eV by applying biaxial tensile strain. Monolayer CrOBr changes from FM state to AFM state when tensile strain increases to 8%. The MAE of monolayer CrOBr reaches a large value of −0.057 meV/f.u. at tensile strain of 8%, which is enhanced by 235% compared to that of unstrained system. The tunable MAE and electronic structure indicate that monolayer CrOBr may be a promising candidate in spintronic devices. • Monolayer CrOBr is FM semiconductor with in-plane magnetic anisotropy of −0.017 meV/formula unit. • The MAE can be enhanced by 235% when biaxial tensile strain reaches 8%. • The band gap varies in the range of 1.547-1.145 eV by applying biaxial tensile strain. [ABSTRACT FROM AUTHOR]

In this paper, spin-polarization and pressure effects on the structural and electronic properties of the 3 d transition-metal mono-borides TM–B (TM=Mn, Fe, Co) have been studied by using both local spin-density approximation (LSDA) and generalized gradient approximation (GGA) within the framework of density-functional theory (DFT). At equilibrium, spin-polarization calculations show that MnB and FeB compounds carry magnetic moment. The non-spin-polarization results show that the non-magnetic state is unstable for MnB and FeB compounds, but a stable non-magnetic phase for CoB compound, which is discussed in the framework of the well-known Stoner criterion. The calculated lattice parameters, bulk moduli, their first-pressure derivatives and magnetic moments agree well with experimental and other theoretical results. Significant differences in volume and in bulk modulus were found between the magnetic and non-magnetic case reached 4%, 22%, respectively. The effect of pressure on the crystal structure reflects in a compression of the unit cell volume with a decreasing in the magnetic moment. The density of states of MnB and FeB ferromagnetic compounds are significantly modified under high pressures. The exchange energy decreases with increasing pressure, at approximately V / V 0 =0.6, the exchange energy becomes absent in ferromagnetic compounds causes mirror in upper and lowers half panels. Finally, we notice that spin-polarization and pressure play a crucially important role in determining the electronic and structural properties of 3 d transition-metal mono-borides. [ABSTRACT FROM AUTHOR]

We study theoretically the tunneling charge conductance in ferromagnet/spin-triplet superconductor junction with the spin–orbit coupling interface. It is shown the symmetry of the conductance about the relative angle between the magnetization in ferromagnet and the d -vector in superconductor is broken due to the presence of the interfacial Rashba spin–orbit coupling. We present the conductance for various cases of the angle. For each angle, the spin-active mechanism provided by the interface is investigated. The interface effects for different spin polarization in the ferromagnet is also considered. [ABSTRACT FROM AUTHOR]

Abstract: In this theoretical work, we perform first-principles calculation to study the geometric, electronic, and magnetic properties of the two-dimensional germanene and silicene hybrid sheet (GeSiHS) saturated with brominate atoms (Br). Although the pristine GeSiHS is semi-metallic, half-saturation on only a single side of Si atoms with Br results in the localized and unpaired electrons in unsaturated Ge atoms, showing long-range ferromagnetic (FM) properties with a high Curie temperature. Interestingly, half-brominated GeSiHS exhibits half-metallic character with 100% spin-polarized currents at the Fermi level. These findings provide the possibility of GeSiHS as promising building blocks for spintronic devices. [Copyright &y& Elsevier]