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In this study, we present results of a comprehensive computational and experimental study of CoFeVAl and CoFeV0.5Mn0.5Al Heusler alloys. It is shown that while CoFeVAl exhibits a fairly large degree of spin polarization, this material is not half-metallic due to the presence of the vanadium spin-down states at the Fermi level. However, replacing 50% of vanadium with manganese results in a nearly half-metallic transition, largely due to the shift of the Fermi level towards occupied states. Moreover, the half-metallicity of CoFeV0.5Mn0.5Al is rather robust in a wide range of considered mechanical strain and under experimentally observed B2-type atomic disorder, thus making this alloy potentially suitable for practical spintronic applications. Both considered alloys exhibit ferromagnetic alignment at larger lattice constants, aside from a relatively small magnetic moment of vanadium which is anti-aligned with the magnetic moments of Co, Fe and Mn. We have synthesized both CoFeVAl and CoFeV0.5Mn0.5Al alloys in cubic structure with some structural disorder using arc melting and annealing. The structural and magnetic properties of the synthesized CoFeV0.5Mn0.5Al alloy are in good agreement with the theoretical calculations but vary slightly from the parent compound. [ABSTRACT FROM AUTHOR]

Ab initio calculations based on density functional theory with the PBEsol method were utilized to examine the influence of hydrogen passivation, vacancies, and dopants on the electronic and magnetic properties of zigzag MgO nanoribbons with a width of w = 6 (6Z-MgONR). Calculations suggested that the 6Z-MgONR–2H configuration, which lacked magnetism and exhibited metallic characteristics, was the most stable configuration. Herein, this configuration with intrinsic defects and impurities were deeply considered. Finds revealed that individual VMg and VO vacancies induced magnetic moments of 0.624 μB and 0 μB, respectively. The calculated formation energy indicated that the occurrence of a single VMg was energetically favored than a single VO. Moreover, the three oxygen atoms adjacent to vacancy displayed inconsistent spin polarization directions, resulting in smaller magnetic moments than bulk MgO. Upon the introduction of Li or N impurities, LiMg under O-rich conditions exhibited the lowest formation energy. This was accompanied by an increase in total magnetic moments to 1.435 μB, which was significantly higher in the case of Mg vacancy. The corresponding spin-resolved charge density clearly demonstrated that the spin polarization was strongly localized at the right edge passivation of H atoms, with a minor contribution from the O atoms closest to the right edge H atoms. The NO/6Z-MgONR–2H configuration also exhibited total magnetic moments of 1.872 μB, but it had a substantially higher defect formation energy compared to the LiMg/6Z-MgONR–2H system. [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 work, CeO 2 nanocrystals with a mixture of distinct morphologies were obtained using different solvents (acetone or ethanol). The (micro)structural, sensing mechanism, and magnetic properties, as well as first-principle calculations were evaluated. XPS reveals that the sample synthesized in acetone exhibited a diminished Ce4+ content (and heightened Ce3+ concentration) compared to the sample synthesized in ethanol. In the case of the syntheses at acetone, sphere-like nanoparticles and nanorods present a predominance of surfaces (111) and (220), while the syntheses with ethanol led to a predominance of surfaces (200) for the sphere-like nanoparticles. Theoretical simulations reveal the spin polarization of f electrons in Ce ions neighboring oxygen vacancies suggests that oxygen vacancies situated at the surface may engender a greater number of magnetic moments compared to those induced by an oxygen vacancy within the bulk. At room temperature, the M S of CeO 2 nanocrystals crystallized in acetone (66.20 emu-g) surpasses that of the CeO 2 nanocrystals obtained in ethanol (24.07 emu-g), which can be attributed to the differing morphologies of the samples. Our findings illustrate that, in addition to the solvent type, the size and morphology of the particles also play a significant role in influencing the sensing mechanism and magnetic properties. Films based on CeO 2 nanocrystals synthesized via MAS using acetone and ethanol revealed a fast response time of 9.6 s and 12 s, with a recovery time of 45.6 s and 87.6 s towards CO gas, respectively, these phenomena are attributed to the presence of oxygen vacancies, which facilitate the adsorption of CO. Our findings are key for facet engineering and may provide new strategies for producing CeO 2 based-materials to be applied in morphology-dependent technologies, such as carbon monoxide (CO) gas sensors. [ABSTRACT FROM AUTHOR]

Randomly mixing ferromagnetic (FM) and antiferromagnetic (AFM) elements in high-entropy alloys (HEAs) can create fluctuating local magnetic moments that influence the energetics of point defects. In this study, we employed first-principles calculations to investigate the influence of magnetic properties on vacancy migration energy in Fe49.5Mn29.4Co10.1Cr10.1C0.9, alongside equiatomic NiCoFeCrMn alloy. By examining structures with paramagnetism, ferromagnetism, and no spin polarization, our study reveals significant impacts of magnetic interactions on vacancy migration barriers, potentially altering the sequence of elemental migration energies if overlooked. In Fe49.5Mn29.4Co10.1Cr10.1C0.9, the order of vacancy migration barriers is Co > Fe > Mn > Cr across all magnetic states, suggesting the dominant roles of atomic properties and inherent chemical bonding. Conversely, the NiCoFeCrMn HEA exhibits a pronounced magnetic state-dependent elemental migration energy order, indicating that magnetic interactions significantly influence vacancy migration behavior in this alloy. In addition, while FM elements generally exhibit higher migration barriers, AFM elements display lower barriers in the investigated Cantor alloys, with notable variations between the studied compositions. These findings underscore the critical role of magnetism in accurate migration energy calculations, which is important for studying chemically biased diffusion and radiation-induced segregation in HEAs. [ABSTRACT FROM AUTHOR]

The spintronic properties of cubic ZrO2 (c-ZrO2) nanosheets with intrinsic defects and transition metal (TM) elements doping have been systematically studied by first-principle calculation. The results show that impurity Fe has the lowest formation energy in each monolayer compared to other defects. The most stable (111) nanosheet, coupled with the higher defect formation energy, tends to disintegrate. Only Zr vacancy (VZr) on the (110) surface or O vacancy (VO) on the (111) surface can generate a ferromagnetic ground state, while other intrinsic defects cannot introduce spin polarization. Ni-doped (110) monolayer cannot introduce a local magnetic moment, while Fe and Co can. The magnetic moments produced by Fe, Co, and Ni in the (111) sheet are 2, 4, and 1 µB, respectively. Further investigation revealed that the magnetism was mainly contributed by the d orbitals of the TM atom and the p orbitals of the surrounding O atoms. Magnetic couplings show that only Co–Co doped monolayers can produce macroscopic magnetism. These are predicted to produce TCs Curie temperature above room temperature when Co–Co distances are 5.070 and 6.209 Å on the (110) surface and 7.170 and 9.485 Å on the (111) surface. The research is beneficial to the refinement of the development of spintronics. [ABSTRACT FROM AUTHOR]

Half-metallic ferromagnetic Heusler alloys attracted much attention in the last few decades due to their significant physical properties as well as its potential applications in spintronic devices. To explore and predict the various physical properties of Co-based Heusler alloy, Co2MnSi (CMS), First principles calculations are of interest and has been used in the present study. Optimized E–V curves represent that CMS alloy is most stable in its magnetic L21 structural phase. The electronic charge density plot represents the ionic bonding along with co-valent character for the compound. DOS and BS calculations shows 100% spin polarization at Fermi level (EF) which confirms the half metallic character of the compound. DOS exhibited the prominent role of Co-3d and Mn-3d electronic states along with Si-2p electronic states. Estimated magnetic moment of Co2MnSi Heusler alloy was found to be ~ 5μB per f. u. which is in line with the Slater-Pauling behaviour. Dynamical stability of Co2MnSi Heusler alloy has also been verified by the phonon dispersion curves which revealed that compound is dynamically stable. Additionally, the physical properties have also been explored as a consequence of SOC and significant changes in electronic and optical properties were observed. The observed significant results of electronic, magnetic, and optical properties of CMS Heusler alloy makes it promising towards potential application in optical and spintronic devices. [ABSTRACT FROM AUTHOR]

We investigate the magnetic properties of La2/3Sr1/3MnO3 (LSMO) membranes released from an SrTiO3 (STO) substrate by selectively etching an Sr4Al2O7 sacrificial buffer layer. The magnetic moment and Curie temperatures (TC) of the released LSMO membranes improve significantly over their substrate-bound counterparts. We attribute these enhancements to suppressing strain and oxygen octahedral rotations that are present in substrate-bound films. Moreover, comparing the magnetic hysteresis loops obtained with magnetic fields applied along several crystallographic orientations demonstrates enhanced (weakened) perpendicular (in-plane) magnetic anisotropy in the released LSMO membranes. Our results contribute to potential applications of released LSMO membranes toward flexible spintronics devices, where high spin polarization and TC are desired. [ABSTRACT FROM AUTHOR]

In this study, we investigate the effects of doping with ∼10 at% of Si, Al, Sn, and Bi on the atomic order, microstructure, and magnetic properties of CoMnSb samples prepared using the arc-melting method. X-ray diffraction, scanning electron microscopy, and magnetometry techniques were employed to derive the structural and magnetic parameters. The samples demonstrate a superstructure with an Fm -3 m space group. They exhibit a saturation moment of 3.71–4.71 μ B per formula unit at 5 K and a Curie temperature ranging from 474 to 507 K. Rietveld refinement performed on the XRD data revealed a possible occupation of magnetic atoms in the vacant 32 f (x ', x ', x ') sites and atomic swapping, both of which may affect the magnitudes of the magnetic moment and Curie temperature. The electrical measurement results show that the grain boundaries and voids govern the conductivity of the samples. The spin polarization of the Si-doped sample was determined based on the grain-boundary magnetoresistance effect, which showed that this sample has a high degree of atomic order, consistent with the low magnetic moment, Curie temperature, and lattice constant. [ABSTRACT FROM AUTHOR]

Based on the first principles of the generalized gradient approximation method, the magnetic and optical properties of Fe-, Ni-doped and (Fe,Ni) co-doped LiNbO 3 crystals are studied. The results show that the mono-doped LiNbO 3 crystals contain magnetic atoms (Fe,Ni) leading to spin polarization, and (Fe,Ni) co-doped LiNbO 3 crystals tend to the ferromagnetic state with △ E F M of − 143 meV. The total magnetic moment of the (Fe,Ni) co-doped LiNbO 3 crystal is 5.97 μ B , and the local magnetic moments of Fe and Ni are 2.99 μ B and 0.93 μ B , respectively. It is interesting that the introduction of the Ga atom makes the ferromagnetic state (△ E F M of − 285.4 meV) of the (Fe,Ni) co-doped LiNbO 3 system more stable than the anti-ferromagnetic state. Although Ga atoms do not contribute to the magnetic moment, the (Fe,Ni,Ga) co-doped LiNbO 3 is more conducive to the spin-polarized state. In addition, with the introduction of Fe, Ni, and Ga atoms, the visible region absorption changes significantly. Non-volatile holographic storage can be achieved by (Fe,Ni) co-doped LiNbO 3 , thus increasing the absorption of the visible light range. In summary, this research provides theoretical guidance for the application of LiNbO 3 crystals in spintronic devices. [ABSTRACT FROM AUTHOR]

A systematic structure and property investigation of MnGen− (n = 3–14) was conducted by means of density functional theory coupled with mass-selected anion photoelectron spectroscopy. This combined theoretical and experimental study allows global minimum and coexistence structures to be identified. It is found that the pentagonal bipyramid shape is the basic framework for the nascent growth process of MnGen− (n = 3–10), and from n = 10, the endohedral structures can be found. For n = 12, the anion MnGe12− cluster probably includes two isomers: a major isomer with a puckered hexagonal prism geometry and a minor isomer with a distorted icosahedron geometry. Specifically, the puckered hexagonal prism isomer follows the Wade–Mingos rules and can be suggested as a new kind of superatom with the magnetic property. Furthermore, the results of adaptive natural density partitioning and deformation density analyses suggest a polar covalent interaction between Ge and Mn for endohedral clusters of MnGe12−. The spin density and natural population analysis indicate that MnGen− clusters have high magnetic moments localized on Mn. The density of states diagram visually shows the significant spin polarization for endohedral structures and reveals the weak interaction between the Ge 4p orbital and the 4s, 3d orbitals of Mn. [ABSTRACT FROM AUTHOR]

A spintronic terahertz (THz) emitter based on rare-earth-transition-metal ferrimagnetic alloys has drawn wide attention due to its prominent THz emission signals at a magnetic compensated state. Here, THz emission spectroscopy is performed in a layered ferrimagnetic/nonmagnetic structure of Ta/Tbx(FeCo)1–x/Pt to investigate the impact of magnetization and spin polarization on THz radiation. Composition and temperature-dependent THz emission signals are observed by an inverse spin Hall effect. The variation of THz amplitude approximately follows the in-plane magnetization in the composition range, yet a nonvanishing THz radiation at the compensation point indicates that net spin polarization dominates the emitted THz electric field rather than net magnetization in this two-sublattice system. A significant gap of 90 K between the compensation point of magnetic moment and spin polarization is found in a Tb0.24(FeCo)0.76 sample, which is a striking difference to that of 25 K in GdCo/Pt THz emitters. We attribute this anomalous gap to the strong intersublattice 3d-5d6s-4f exchange interaction of TbFeCo alloy; thus, the contribution of spin polarized Tb 4f electrons should be reconsidered after fs laser pulse excitation. These results gain insight into spin dynamics of complex multisublattice systems and pave the way for further optimized spintronic THz emitters to modulate THz radiation efficiently. [ABSTRACT FROM AUTHOR]

To meet the current requirements of diluted magnetic semiconductors (DMSs) resulting from continuous advancements in spintronics, designing d0 DMSs with high stability, spin polarization, and Curie temperature is essential. Present research on introducing d0 magnetism is limited to monatomic doping, lacking regulation measures for local magnetic moments and long range magnetic coupling. Herein, an adjacent doping strategy is employed to introduce degrees of freedom for tuning the magnetic properties of d0 DMSs. It is observed that by introducing Si and O atoms as central and adjacent dopants, respectively, the intrinsically nonmagnetic hexagonal boron nitride (h-BN) exhibits significant local magnetic moments. Furthermore, it is observed that the ionization energy, total magnetic moment, magnetic coupling, and Curie temperature of the doped h-BN are susceptible to the Si–O coordination. Subsequently, a magnetic half-metal (Si–O3-doped h-BN) with high thermal stability, 100% spin polarization, long range ferromagnetic coupling, and high Curie temperature is designed through high Si–O coordination doping. This study proposes a feasible approach for introducing tunable d0 magnetism using the design of Si–O adjacent-doped h-BN as an example. [ABSTRACT FROM AUTHOR]

We propose a method of cooling nuclear spin systems of solid-state nanostructures by applying a time-dependent magnetic field synchronized with spin fluctuations. Optical spin noise spectroscopy is considered a method of fluctuation control. Depending on the mutual orientation of the oscillating magnetic field and the probe light beam, cooling might be either provided by dynamic spin polarization in an external static field or result from population transfer between spin levels without build-up of a net magnetic moment ("true cooling"). [ABSTRACT FROM AUTHOR]

The structural, elastic, electronic, and magnetic properties of the CrCoSi, MnCoSi parent half-Heusler (HH) alloys, and their CrMnCo2Si2 derivative double half-Heusler (DHH) compound are studied, utilizing the augmented plane wave method, which is based on density functional theory and implemented in the WIEN2k code. The stability of HH structure of the CrCoSi and MnCoSi alloys has been checked for their non-magnetic and ferromagnetic phases, leading to that the latter phase of the type I arrangement is the most stable. The CrMnCo2Si2 DHH alloy, derivative from the found structural and magnetic ground states of CrCoSi and MnCoSi HH alloys, is constructed and investigated. This DDH as well as its CrCoSi parent HH are found to be resistant to deformation and can be classified as ductile materials, whereas the MnCoSi compound is brittle. By the gradient generalized approximation (GGA), the electronic structures of CrCoSi, MnCoSi, and CrMnCo2Si2compounds exhibit a metallic behavior in the spin-up channel and a semiconducting behavior in the spin-dn channel, with band gaps (half-metallic gaps) of 0.851(0.020), 0.852(0.021), and 0.531(0.002) eV, respectively. The half-metallicity of CrMnCo2Si2 DHH is retained with smaller (larger) band gap (half-metallic gap) of 0.38(0.106) eV than that of GGA, using GGA + U approximation. In addition, the total magnetic moments are found to be 1, 2, and 3 µB for CrCoSi, MnCoSi, and CrMnCo2Si2, respectively. Therefore, these alloys can be good candidates for spinitronic applications due to their half-metallicity. [ABSTRACT FROM AUTHOR]

Density functional theory in the framework of generalized gradient approximation (GGA) of Perdew–Burke–Ernzerhof to investigate the effects of some selected transition metal (TM) and rare‐earth metal (RE) dopants on the electronic and magnetic properties of a 2D molybdenum disulfide (MoS2) monolayer is reported. The results demonstrate that it is energetically stable to incorporate Ni and Cu in MoS2 structure under Mo‐rich conditions. The pristine MoS2 monolayer has a calculated direct bandgap of 1.70 eV and experiences significant reduction in the gap due to the defects. There is observed induced magnetic behavior due to the tight binding effect originating from the localized dopants and the nearest‐neighbor Mo atoms, with magnetic moments ranging between 0.82 and 3.00 μB. Some of the dopants result in 100%$$ spin polarization which is useful for engineering spin filter devices on magnetic MoS2 nanostructures. [ABSTRACT FROM AUTHOR]

Using the first-principles calculations based on density functional theory (DFT) within the generalized gradient approximation (GGA), Ti2RuAl full-Heusler compound is studied. The electronic structure, magnetic, and optical properties of Ti2-based full Heusler compound Ti2RuAl are calculated and analyzed using the Wien2k package. The CuHg2Ti-type structure is found to be more favorable than the AlCu2Mn-type structure for this compound. The Ti2RuAl Heusler compound exhibits a ferrimagnetic half-metallic behavior with the total magnetic moment of 1 µB at the equilibrium lattice constant 6.24 Å. The total magnetic moment of Ti2RuAl is in agreement with the Slater-Pauling rule mtot = ztot–18 and hence has integral magnetic moments which is due to 100% spin polarization at Fermi energy. Ti2RuAl has an energy gap in the spin-down channel of 0.229 eV. This compound keeps a 100% of spin polarization for lattice constant change in the range of 5.8–6.5 Å. The Curie temperature of Ti2RuAl is estimated to be 451 K using the mean field approximation (MFA). In addition, optical properties like dielectric function, reflectivity, energy loss function, absorption coefficient, and optical conductivity are calculated. [ABSTRACT FROM AUTHOR]

A subclass of ternary intermetallic known as Heusler compounds is being employed in the steel industry to increase material strength. This study examines the structural, electrical, optical, and magnetic properties of Co2VZ (Z=Al, Bi, Ge, Si) compounds using two different methods. First is full potential linearized augmented plane wave (FP-LAPW) method by WIEN2k and second is pseudo potential method by Atomic Tool Kit-Virtual Nano-Lab. The equivalent energy gaps in the minority-spin of Co2VZ (Z= Al, Bi, Ga, Ge) with WIEN2k code, which displays 100% spin polarization, are 0.703, 0.384, 0.186, and 0.67 eV near to the Fermi level. Furthermore, it is discovered that these compounds are absolutely half-metallic ferromagnetic (HMF). With the exception of Co2VBi, which exhibits metallic properties, the aforementioned compounds exhibit 0.525, 0.0, 0.553, and 0.786 eV band gaps in the ATK-VNL code and indicate 100% spin polarization. The magnetic moments of the compounds Co2VZ (Z= Al, Bi, Ga, Ge) are found to be 2.976, 4.003, 1.989, and 3.001 µB, respectively, in the WIEN2k code. The relative magnetic moments of the aforementioned compounds are also 1.991, 3.947, 1.999, and 2.997 µB, according to the ATK-VNL code. [ABSTRACT FROM AUTHOR]

This paper studies the quark condensate, magnetic moment, magnetic polarization, and magnetic susceptibility in a strong external magnetic field by employing the Dyson–Schwinger equations (DSE). The results show these physical quantities as functions of the magnetic field. We note that the quark's spin polarizations are approximately proportional to the magnetic field magnitude. For comparison, we investigate the magnetic moments and susceptibility of the nucleon in the constituent quark model framework and demonstrate that both these quantities increase as the magnetic field rises. [ABSTRACT FROM AUTHOR]

Herein, a comparative computational study inquiring about ground state magnetic properties of a nanometer‐size bowtie graphene quantum dot with an AA‐stacking bilayer trapezoid counterpart based on the single‐orbital Hubbard model and density functional theory (DFT) is presented. The structures have an antiferromagnetic ground state with a 1‐to‐1 correspondence between the local spin polarizations of the two systems. The tight‐binding energy spectra look different. However, a similar fashion in the energy spectra emerges after considering the Hubbard interaction term. A comparison between the spatial distributions of edge states shows that the wave functions in both structures are sublattice polarized by proposing a specific unit cell in the bilayer case. In addition, the on‐site coulombic repulsion consequence on the rising of magnetization and the size of the local magnetic moment has been considered. [ABSTRACT FROM AUTHOR]

Recently, 2D Janus structures containing oxygen have attracted great attention from researchers. Herein, the ZrXO (X = S and Se) Janus monolayers are investigated using first‐principles calculations based on the projector augmented wave (PAW). ZrSO and ZrSeO single layers are dynamically and thermally stable, and exhibit the indirect gap semiconductor character with a bandgap of 1.91(2.88) and 1.09 (1.88) eV, respectively, as determined by the standard PBE (hybrid HSE06) functional. The charge transfer process from Zr atom to IVA‐atoms is confirmed by means of the charge density difference and Bader population analysis. Studied 2D materials exhibit good absorption in a wide energy range from visible to ultraviolet regimes with larger absorption coefficient reaching to the order of 105 cm−1. To magnetize the ZrXO monolayers for possible spintronic applications, fluorine (F) and chlorine (Cl) doping is proposed. Significant magnetic properties with total magnetic moments ≈1 μB are obtained. Besides, high spin polarization around the Fermi level is also induced as a result of the feature‐rich half‐metallic or magnetic semiconductor natures. Results presented herein introduce ZrSO and ZrSeO monolayers as prospective 2D materials to be applied high‐performance nano optoelectronic and spintronic devices. [ABSTRACT FROM AUTHOR]

The structural, electronic, magnetic, and optical properties of Co‐ and Mn‐adsorbed γ‐GeSe have been studied comprehensively via first‐principles density functional calculations. It is found that the most stable adsorption configuration is that Co and Mn are on the top of the hexagonal hollow in the second Ge layer. After Co and Mn adsorption, γ‐GeSe becomes magnetic with 1 μB and 3 μB magnetic moment, which mainly comes from mainly the Co(Mn)‐d, Ge‐s, Ge‐p, and Se‐p states. In particular, the optical absorption in the low‐energy range is greatly enhanced by Co and Mn adsorption and results in interesting spin‐dependent absorption in low‐energy region due to the strong electron transition at the spin‐down channel, which makes them attractive candidates for spin‐optoelectronic devices. [ABSTRACT FROM AUTHOR]

Accelerating insoluble Li2S2−Li2S reduction catalysis to mitigate the shuttle effect has emerged as an innovative paradigm for high‐efficient lithium‐sulfur battery cathodes, such as single‐atom catalysts by offering high‐density active sites to realize in situ reaction with solid Li2S2. However, the profound origin of diverse single‐atom species on solid‐solid sulfur reduction catalysis and modulation principles remains ambiguous. Here we disclose the fundamental origin of Li2S2−Li2S reduction catalysis in ferromagnetic elements‐based single‐atom materials to be from their spin density and magnetic moments. The experimental and theoretical studies disclose that the Fe−N4‐based cathodes exhibit the fastest deposition kinetics of Li2S (226 mAh g−1) and the lowest thermodynamic energy barriers (0.56 eV). We believe that the accelerated Li2S2−Li2S reduction catalysis enabled via spin polarization of ferromagnetic atoms provides practical opportunities towards long‐life batteries. [ABSTRACT FROM AUTHOR]

Accelerating insoluble Li2S2−Li2S reduction catalysis to mitigate the shuttle effect has emerged as an innovative paradigm for high‐efficient lithium‐sulfur battery cathodes, such as single‐atom catalysts by offering high‐density active sites to realize in situ reaction with solid Li2S2. However, the profound origin of diverse single‐atom species on solid‐solid sulfur reduction catalysis and modulation principles remains ambiguous. Here we disclose the fundamental origin of Li2S2−Li2S reduction catalysis in ferromagnetic elements‐based single‐atom materials to be from their spin density and magnetic moments. The experimental and theoretical studies disclose that the Fe−N4‐based cathodes exhibit the fastest deposition kinetics of Li2S (226 mAh g−1) and the lowest thermodynamic energy barriers (0.56 eV). We believe that the accelerated Li2S2−Li2S reduction catalysis enabled via spin polarization of ferromagnetic atoms provides practical opportunities towards long‐life batteries. [ABSTRACT FROM AUTHOR]

The changes in the magnetic and half-metallic characters of the structures formed by the doping of Ag, Cd, Y, Zr, and Nb atoms at the ratios of x = 0.25 and 0.125 to WSn alloy were investigated. While the spin-up states of all alloys showed metallic character, energy band gaps were observed in the spin-down states, except YSn alloy. Of the 10 structures, 84.10% spin polarization was obtained only in the Zr0.25W0.75Sn alloy, and the spin polarizations were 100% in all remaining alloys. Band calculations were made with both GGA and GGA + mBJ methods. When the GGA + mBJ method was used, an increase in band gaps was observed in proportion to the increase in Fermi energy levels. In addition, the obtained 3, 4, 5, 6, 7 μB/f.u. magnetic moments for M0.25(M = Ag, Cd, Y, Zr, Nb)W0.75Sn alloys, respectively, and the calculated magnetic moment per unit formula of 5.5, 6, 6.5, 7, 7.5 μB/f.u. for M0.125(M = Ag, Cd, Y, Zr)W0.875Sn alloys support their fields that can be used in spintronic applications. The magnetic moment values obtained with GGA-U (U = 1, 2, 3, 4 eV) calculations showed that while the magnetic moment values of Zr0.25W0.75Sn and Nb0.25W0.75Sn alloys were preserved, they directly increased the magnetic moments of some alloys. These high ratios of polarization, band gaps, and magnetic moments make all alloys ideal materials for use in spintronic applications. [ABSTRACT FROM AUTHOR]

Heusler alloys based on 4d-elements are relatively less explored though they are known to host interesting electronic/magnetic properties useful for future spintronics applications. Here, we report a comparative study of the structural and magnetic properties of FeRuVSi (FRVS) and FeRuVGe (FRVG) using experimental and theoretical tools. Magneto-transport measurements have also been carried out to probe the role of magnetism on their transport behaviour. Room temperature (T) X-ray diffraction data reveals cubic crystal structure (space group No. 216) with B 2 type antisite disorder between Fe and Ru sites in both the alloys. They show ferromagnetic behaviour below the Curie temperature (T C) 84 K for FeRuVSi and 57 K for FeRuVGe respectively. The field dependence of magnetization at low-T shows saturating (nearly saturating) behaviour for FRVS (FRVG). Transport measurements show metallic behaviour with a sharp reduction in the resistivity near T C. Ab-initio calculations predict nearly half metallic behaviour with ∼ 87 % and ∼ 89 % spin polarization for FRVS and FRVG in their ordered states. The inclusion of antisite disorder changes the magnetic configuration, leading to a visible decrease in the magnetic moment and spin polarization. The calculated net moment and the transport properties agree fairly well with those observed experimentally. These results confirm the importance of disorder in determining the intrinsic properties of these alloys. Such combined studies help in the identification of more novel quantum materials suitable for future spintronic applications. ● We present a comparative study of the magnetic, transport, and electronic properties of FeRuVZ (Z = Si, Ge) Heusler alloys. ● Disorder increases the symmetry of the FeRuVSi Heusler alloy to L 2 1 type, higher than that in FeRuVGe. ● The magnetization goes from saturating to nearly saturating behaviour when Si is changed to Ge. ● High spin polarization and nearly half metallic behaviour in the ordered state in both the alloys. [ABSTRACT FROM AUTHOR]

The weak magnetic properties of Ni 0.25 NbSe 2 are attributed to the delocalized nature of Ni-3 d electrons and hence poor spin polarization. [Display omitted] • Ni x NbSe 2 with x = 0, 0.05, 0.1, 0.15, 0.2 and 0.25 were synthesized and observed that Ni intercalation limit is 25 %, beyond which NiSe phase segregates. • A phase transition is observed beyond x = 0.20 in Ni x NbSe 2 with a 2 a o × 2 a o × 1 c o order superstructure. • Theoretical calculation on Ni 0.25 NbSe 2 shows that the magnetic spins are very weakly spin-polarized and the Ni-3 d states are more delocalized. • Magnetic measurements on Ni x NbSe 2 (x = 0.05, 0.1, 0.2, 0.25) shows very small magnetic moment at low temperature for all the compounds attributed to the delocalized nature of Ni-3 d electrons, which is conformed from the theoretical studies. The article presents the synthesis, structural and magnetic properties of Ni x NbSe 2 (x = 0, 0.05, 0.1, 0.15, 0.2, 0.25). The intercalation limit of Ni in NbSe 2 is found to be 25 mol%, above which NiSe appears as a binary impurity phase. Single crystal X-ray diffraction studies show that all the compounds crystallize in the hexagonal P6 3 /mmc space group. However, there is a distinct phase transition beyond x = 0.20 with Ni intercalation in Ni x NbSe 2. The Ni x NbSe 2 compounds crystallized in the parent 2H phase with x value between 0 ≤ x ≤ 0.2. Subsequently, the phase transforms into the 2H(I) phase with an order superstructure of 2 a o × 2 a o × 1 c o for 0.20 ≤ x ≤ 0.25 in Ni x NbSe 2. The superstructure formation is attributed to the occupation of Ni at the alternate octahedral voids present in the van der Waals gap of the NbSe 2. The XPS results and theoretical analysis clearly show that the intercalation of Ni results in a more metallic character in Ni x NbSe 2. Magnetic measurements on Ni x NbSe 2 (x = 0.05, 0.1, 0.2, 0.25) shows very small magnetic moment at low temperature for all the compounds. Theoretical calculation on Ni 0.25 NbSe 2 shows that the Ni-3 d electrons are delocalized and are very weakly spin-polarized, which may be the reason for the experimentally observed weak magnetism in these compounds. [ABSTRACT FROM AUTHOR]

The FP-LAPW method is used to examine the physical properties of Fe–Pd binary intermetallic compounds. The calculated formation enthalpies indicate that FePd and FePd 3 compounds are thermodynamically stable in L1 0 and L1 2 phases, respectively, and the ferromagnetic Fe 3 Pd can be formed in a tetragonal Z1 structure with a small negative formation enthalpy. The elastic coefficients and their related parameters show that all compounds are mechanically stable and ductile in nature. The FePd-L1 0 is the harder compound and Fe 3 Pd-Z1 exhibits the highest anisotropy. The band structure, the TDOS profile and the charge density distribution show that these compounds are ferromagnetic with a metallic character and covalent-metallic bonds. The PDOS shows that the Pd- 4d and Fe- 3d states are dominant, and the asymmetry of Fe- 3d states is behind the system strong spin polarization. The calculated magnetic moments agree well with previous theoretical results. The thermodynamic parameters are determined using the quasi-harmonic Debye model. [ABSTRACT FROM AUTHOR]

[Display omitted] Incorporating magnetic species, magnetic functional groups or additives, into polymer hosts is an effective method for synthesizing magnetic polymers. Polymers can gain magnetic moments not solely through magnetic coupling but also via the induction of Coulombic excitation. Attachment of the magnetic side-groups to the polymer backbone increases orbital localization in repeat units. This will bring two competing effects. The orbital localization will increase the intra-site Coulomb interaction, which increases magnetic moments in repeat units. Oppositely, the orbital localization also increases the energy splitting between orbitals on the polymer backbone and on side-groups, suppressing thus the magnetic moments of repeat units. However, a preference for low-spin states in the polymer units emerges when a substantial split in orbital energy occurs due to a strong coupling, consequently suppressing the magnetic moment. On the contrary, a minimal split in orbital energy within the polymer units can readily induce a high-spin state and generate a magnetic moment. However, in such cases, the Coulomb interaction triggered by the interconnected magnetic moieties might be too weak to produce a magnetic moment in the polymer. To explore this trade-off, we have proposed a theoretical two-level model aimed at elucidating the decision-making process of experimentalists during the synthesis of magnetic polymers. We also found that the dimerization of the polymer backbone together with the phonon dependence of spin–spin interaction between near-neighbor repeat units increases magnetic moments. As the magnetic responses arising from Coulombic interactions in polymers are intricately linked to carrier density, properties of the magnetic polymers acting as an active layer of a field-effect transistor can be tuned by the gate field, which controls the charge carrier density in the transistor transport channel. [ABSTRACT FROM AUTHOR]

This study employs density functional theory (DFT) using Wien2k to comprehensively analyze the essential properties of two half-Heusler alloys, KCrSi and KCrGe. Our findings demonstrate that the ferromagnetic Type 2 configuration exhibits superior stability over non-magnetic and antiferromagnetic states for all KCrZ (Z = Si, Ge) alloys. These alloys exhibit complete spin polarization and half-metallic character, with calculated magnetic moments of 3 μB for both KCrSi and KCrGe. The Curie temperature (T C) is determined using the mean field approximation. Mechanical stability is assessed through second-order elastic constants (SOECs), and electronic properties are analyzed using local spin density approximation (LSDA), Perdew-Burke Generalized Gradient Approximation (PBE-GGA), and Tran-Blaha modified Becke-Johnson (TB-mBJ) schemes, confirming the retention of the half-metallic nature. The negative enthalpy of formation (ΔH) suggests material stability. The use of semi-classical Boltzmann theory, incorporated through the sophisticated scheme of BoltzTraP, explores transport coefficients. High pressures and temperature discrepancies in thermodynamics are considered by implementing the quasi-harmonic Debye approximation to illustrate stability. Finally, optical properties are summarized to assess the applicability of this alloy for optoelectronic applications. The overall characteristics of these particular alloys suggest potential applications in sustainable thermoelectric and optoelectronic features. • The stability in cubic structure is established with the help of structural optimization, and mechanical stability criteria. • The high Seeback coefficient and low thermal conductivity yield a high figure of merit ZT at 900 K. • The alloy has potential applications in thermoelectric technology and optoelectronic devices. [ABSTRACT FROM AUTHOR]

[Display omitted] • The coupling effect of the BCC-B2 transition and Mn occupancies has been studied. • The BCC-B2 transition intensified the magnetic interaction between Fe and Mn atoms. • The increased covalent bonding component and Peierls stress enhanced the brittleness. • VEC, spin polarization, and Mn content correlate with the contradictory relationship. The magnetism-ductility contradictory relationship presents a significant challenge in the development of magnetic alloys. The impact of the BCC-B2 transition, along with Mn site occupancy, on magnetism and ductility have been investigated by using first-principles calculations. The calculations involved the evaluation of magnetic moments, density of states (DOS), phase stability and ductility of FeCoMn alloys. The results of binary alloys confirm the enhancement of magnetism due to the BCC-B2 transition. Furthermore, the ordering phase transition can strengthen the magnetic interaction between Fe and Mn atoms, which is associated with minimal variations in the density of states of Fe and Mn in the B2 structure. Regarding the ductility of FeCoMn alloys, two factors contribute to increased brittleness. Firstly, the increased covalent component in bonding, as a result of the strong hybridization between different elements, leads to an increased brittleness. Secondly, the increased Peierls stress provides a larger resistance to dislocation motion, which also contributes to the increased brittleness. Finally, the Pearson correlation coefficients and data analysis indicate that VEC, spin polarizations and Mn content provide major contributions to the contradictory relationship between magnetism and ductility. [ABSTRACT FROM AUTHOR]

We investigated the Ge-composition (Îł) dependence of the saturation magnetization of Co2Fe(Ga, Ge) (CFGG) thin films and the magnetoresistance (MR) ratio of CFGG-based current-perpendicular-to-plane giant magnetoresistance (CPP-GMR) devices together with first-principles calculations of the electronic states of CFGG. Theoretical calculations showed that spin polarization is highest at the stoichiometric composition Îł = 0.56 in Co2Fe1.03Ga0.41Ge Îł and that it decreases in off-stoichiometric CFGG, mainly due to the formation of CoFe antisites for Ge-deficient compositions and FeCo antisites for Ge-rich compositions, where CoFe (FeCo) indicates that Co (Fe) atoms replace the Fe (Co) sites. The saturation magnetic moment (ÎĽ s) per formula unit decreased monotonically as Îł increased from 0.24 to 1.54 in Co2Fe1.03Ga0.41Ge Îł. The ÎĽ s was closest to the Slaterâ€"Pauling value predicted for half-metallic CFGG at the stoichiometric composition Îł = 0.56, indicating that stoichiometric CFGG has a half-metallic nature. This is consistent with the result for the theoretical spin polarization. In contrast, the MR ratio of CFGG-based CPP-GMR devices increased monotonically as Îł increased from 0.24 to 1.10 and reached an MR ratio of 87.9% at the Ge-rich composition Îł = 1.10. Then, the MR ratio decreased rapidly as Îł increased from 1.10 to 1.48. Possible origins for the slight difference between the Ge composition at which the highest MR ratio was obtained (Îł = 1.10) and that at which the highest spin polarization was obtained (Îł = 0.56) are improved atomic arrangements in a Ge-rich CFGG film and the reduction of effective Ge composition due to Ge diffusion in the GMR stacks. [ABSTRACT FROM AUTHOR]

The ab initio investigations of Mx (M = Y, Zr, Nb)–Sc1-x–Sn diluted ternary alloys were calculated for x = 0.25, 0.125, and 0.0625 ratios in GGA and GGA + mBJ methods. Half-metallic band gaps were observed in the spin-up electron states. Only the spin-up electrons of the Nb0.25Sc0.75Sn alloy cut the Fermi energy level and reduced the spin polarization amount to 75.24%. Band gap values were also obtained in both GGA and GGA + mBJ methods. When the GGA + mBJ method was used, an increase was observed in the half-metallic characters of the alloys. Therefore, all the alloys were obtained as true half-metallic ferromagnetic materials. Total magnetic moment values were obtained as 4.00 μB/f.u. in all ratios of Y–Sc–Sn alloys. Since Y and Sc are in the same period, this result is expected for half-metallic alloys. While the total magnetic moment was 3.00 μB/f.u. for the 0.25 ratio in the Zr–Sc–Sn alloy, it was obtained as 3.50 μB/f.u. and 3.75 μB/f.u. for the 0.125 and 0.0625 ratios, respectively. While the total magnetic moment of the Nb0.25Sc0.75Sn alloy was obtained as 1.923 μB/f.u., the magnetic moment values increased to 3.00 μB/f.u. and 3.50 μB/f.u., respectively, when the amount of Sc increased. In short, considering both their electronic and magnetic properties, Mx (M = Y, Zr, Nb)-Sc1-x-Sn ternary alloys are quite suitable for spintronic applications. [ABSTRACT FROM AUTHOR]

First-principle calculations were used to simulate the changes in magnetic parameters and interatomic charge density in the crystal structure of yttrium iron garnet (YIG) caused by Ca–Sn co-doping. The simulation results illustrate that Ca and Sn have no spin polarization in the crystal, and the charge density among ions tends to increase with doping concentration. A solid-state reaction method was employed to prepare YIG with varying concentrations of Ca–Sn co-doping. The saturation magnetization ($4\pi M_{s}$) of the material shows an initial increase and then decrease as the number of doping increases. This phenomenon of increment in $4\pi M_{s}$ at first could be accounted for the increase of the net magnetic moment of material. The reduction in $4\pi M_{s}$ could be interpreted as the content of Fe3+ ($5~\mu \text{B}$) decreases, while the Fe2+ ($4~\mu \text{B}$) in the material becomes the primary portion when the concentration of doping exceeds 0.10. [ABSTRACT FROM AUTHOR]

In this work, silicon carbide layers containing silicon vacancies are grown by the Method of Coordinated Substitution of Atoms (MCSA). The main idea of this fundamentally new method is that silicon vacancies are first created in silicon, which is much simpler, and only then is silicon converted into silicon carbide by chemical reaction with carbon monoxide. The dielectric function of silicon carbide containing silicon vacancies, grown on both n- and p-type silicon substrates, is measured for the first time. The density functional method in the spin-polarized approximation is used to calculate the dielectric function of silicon carbide containing silicon vacancies. It is shown that the influence of the magnetic moment of vacancies on the dielectric function is decisive. Qualitative correspondence of the computational model to the obtained experimental data is demonstrated. It is discovered that silicon vacancies make silicon carbide much less transparent. It is shown that the imaginary part of the dielectric function is described as a sum of oscillatory peaks in the form of the Gaussian functions. Vacancies lead, as a rule, to one or two additional peaks. According to the amplitude and position of the additional peaks, it is possible to qualitatively estimate the concentration of vacancies and their charge. [ABSTRACT FROM AUTHOR]

In this work, we have studied the structural, thermal, elastic and magnetoelectronic properties of FeNiMnZ (Z = Al, Si) Heuslers under pressure using the pseudo-potential plane wave method. The structural optimization was performed by considering three atomic arrangements in magnetic and non-magnetic states. It was found that FeNiMnZ Heuslers are chemically stable and crystallize in the ferromagnetic YI-type structure. At zero temperature (0 K) and zero pressure (0 GPa), the obtained lattice constant (a) and bulk modulus (B) are in good accordance with the literature. The determined elastic constants (Cij), Pugh's ratio (B/G), and universal elastic anisotropy index (AU) under pressure reveal that FeNiMnZ Heuslers are mechanically stable up to 76 GPa, behave in a ductile manner, and exhibit a notable elastic anisotropy, respectively. The band structure analysis shows that FeNiMnAl Heusler compound changes from perfect half-metallic to a metallic nature at 50.2 GPa, while FeNiMnSi Heusler compound keeps its metallicity throughout the considered pressure range. The spin polarization and total magnetic moment of FeNiMnAl (FeNiMnSi) material decrease under pressure varying from 50.2 to 88 GPa (from 0 to 80 GPa). Below 50.2 GPa, FeNiMnAl material exhibits 100% spin polarization and a total magnetic moment of 4μB, which makes it hopeful in spintronic applications. [ABSTRACT FROM AUTHOR]

The Stern–Gerlach (SG) effect is well known as the spin-dependent splitting of a beam of atoms carrying magnetic moments by a magnetic-field gradient, leading to the concept of electron spin. Antiferromagnets can accommodate two magnon modes with opposite spin polarizations, which is equivalent to the spin property of electrons. Here, we propose an all-magnonic SG effect in an antiferromagnetic magnonic system, where a linearly polarized spin-wave beam is deflected by a straight Dzyaloshinskii–Moriya interaction (DMI) interface into two opposite polarized spin-wave beams propagating in two discrete directions. Moreover, we observe bi-focusing of antiferromagnetic spin waves induced by a curved DMI interface, which can also spatially separate thermal magnons with opposite polarizations. Our findings provide a unique perspective to understand the rich phenomena associated with antiferromagnetic magnon spin and would be helpful for polarization-dependent application of antiferromagnetic spintronic devices. [ABSTRACT FROM AUTHOR]

In this paper, the first principle method based on density functional theory is used to calculate the electronic structure, magnetic moment, and charge density and differential charge density of the thin film growth system whose epitaxial relation is CoSi (001)//MgO (001). The results show that when the lattice constants a and b of CoSi crystal are set as 0 .84224 nm and C =0.28135 nm, the energy of the system is the lowest and the most stable equilibrium state is reached. It can be seen from the spin polarization band diagram, total electron state density and fractal density that the guide band bottom and valence band top of the CoSi epitaxial film overlap significantly, thus showing the gold property and producing obvious spin cracking phenomenon near the Fermi level. The valence band top is mainly composed of THE 3d7 state electrons of Co, while the conduction band bottom is mainly composed of the 3p state electrons of Si. At the same time, it can be seen from the state density that the phenomenon of pseudo energy gap is generated. The Co-3d state electrons not only mainly contribute to the state density, but also are speculated to be the main factor for the magnetic generation of the film. According to the calculated Mulliken charge and charge density, electrons are transferred from Si to Co, and Co ACTS as the electron acceptor, forming an anti-bonding state between Co and Si, and forming a covalent bond structure between Co and Si. The CoSi under this epitaxial relationship is ferromagnetic and the total magnetic moment is 0.52 μB. [ABSTRACT FROM AUTHOR]

We studied how the presence point defects could modify Black-Phosphorene/MoS 2 van der Waals heterostructures' optoelectronic properties. Specifically, we looked into the effects of various vacancy defects created by removing phosphorus atoms from Black-Phosphorene/MoS 2 van der Waals heterostructures. We identified seven types of vacancies based on their formation energy and then analyzed their electronic and optical properties using density functional theory (DFT). Our findings revealed that double vacancies are the most likely structural defect and that mono vacancies and tetra vacancies result in a local spin magnetic moment of approximately 1.0 μ B. These results emphasize the importance of considering spin polarization in these systems. We also observed that the band gap in the heterostructure is reduced compared to pristine phosphorene, indicating that the interaction with MoS 2 plays a significant role in modulating the electronic and optical properties of the defective Black-Phosphorene/MoS 2 van der Waals heterostructures. [Display omitted] • Vacancy defects modify the band gap energy depending on the number of them. • Low spin magnetic moment are induced only with odd number of phosphorous vacancy. • The computed spin magnetic moment depend to the parity of removed atoms number. • Black-Phosphorene/MoS 2 heterostructure has infrared, visible and ultraviolet optical response. [ABSTRACT FROM AUTHOR]

We used first-principles density functional theory (DFT) to study the optical, electronic, and structural properties of RbTaO 3 cubic perovskite in both bulk and surface (0 0 1) forms. The RbTaO 3 bulk system exhibited semiconducting behaviour with a band gap (E g) of 2.20 eV. It showed weak reflectivity, excellent optical conductivity, and high absorption of incident energetic photons, indicating its potential for optoelectronic applications. For the surface (0 0 1), two RbO and TaO 2 terminations were constructed. We calculate the atomic displacement (ΔZ) and surface energy (E surf) for both terminations. The RbO- and TaO 2 -(0 0 1) terminated surfaces appeared half-metallic ferromagnetic (HMF) with a spin magnetic moment of integer value 1.00 μ β and fully spin polarization (SP) 100 %. The E g for RbO- and TaO 2 -terminations were 2.60 eV and 2.30 eV, respectively, suggesting their potential for spintronics. We also analysed and compared the optical properties and atomic populations (Q) and their variation (ΔQ) for (0 0 1)-RbTaO 3 terminations with the bulk system. • The RbTaO 3 bulk system appears to have semiconducting behaviour with a band gap (E g) of 2.20 eV. • New RbO- and TaO 2 -terminations appeared half-metallic ferromagnetic (HMF) with a spin magnetic moment of 1.00 μ β. • The band gap (Eg) for RbO- and TaO 2 -terminations is 2.60 eV and 2.30 eV, respectively. [ABSTRACT FROM AUTHOR]

[Display omitted] • PtSe 2 monolayer is a non-magnetic indirect-gap semiconductor 2D material. • Either half-metallic or magnetic semiconductor natures are induced by doping with TMX n clusters. • Magnetic properties depend on the spin ordering in the incorporated clusters. • TMN n clusters act as charge gainers, meanwhile TMP n clusters lose charge. • Efficient methods to make new highly spin-polarized 2D materials towards spintronic applications are proposed. In this work, doping with TMX n (TM = Mn and Fe; X = N and P, n = 3 and 6) clusters is proposed to modify the electronic and magnetic properties of PtSe 2 monolayer. Pristine PtSe 2 monolayer is a non-magnetic two-dimensional (2D) semiconductor material with indirect band gap of 1.40(2.01) eV obtained from PBE(HSE06)-based calculations. PtSe 3 -type multivacancies lead to the monolayer magnetization with total magnetic moment of 0.54 μ B , where Pt and Se atoms around defect sites produce mainly the system magnetism. In contrast, no magnetism is induced by PtSe 6 -type multivacancies. The substitutional incorporation of TMX n clusters magnetizes significantly PtSe 2 monolayer, where both TM and X atoms originate mainly the magnetic properties. Depending on the spin orientation in the clusters, total magnetic moments between 0.00 and 8.00 μ B are obtained. All the doped D TMX n systems exhibit strong spin polarization around the Fermi level, which is derived mainly from the outermost TM- 3 d , N- 2 p , and P- 3 p orbitals. Consequently, either half-metallicity or magnetic semiconductor behavior can be induced, depending on the nature of TMX n cluster. Further, the Bader analysis indicates that TMN n clusters act as charge gainers due to the more electronegative nature of N atoms in comparison with Se atoms, meanwhile TMP n clusters transfer charge to the host PtSe 2 monolayer. Our study may introduce the cluster doping in PtSe 2 monolayer as efficient method to create new highly spin-polarized 2D materials towards spintronic applications. [ABSTRACT FROM AUTHOR]

• Highly ordered L2 1 type heusler alloy film on cu substrate. • Near stoichiometric Co 2 FeSn films by electrodeposition. • High magnetic moment, high T C and high effective anisotropy films. • Co 2 FeSn films (320 nm −1400 nm thick) with high crystalline order. • Minority band gap close (∼0.05 eV) to fermi level. Co 2 FeSn films have been electrochemically deposited on polycrystalline Cu substrates in potentiostatic mode. Processed films with thicknesses of 320 nm, 780 nm, and 1400 nm exhibited highly ordered L2 1 type crystal structure with saturation magnetizations of 1023.38 kA/m (5.08 ± 0.04 μ B /f.u.), 1035.31 kA/m (5.14 ± 0.04 μ B /f.u.) and 1044.34 kA/m (5.18 ± 0.04 μ B /f.u.) at 5 K and 965.00 kA/m (4.79 ± 0.04 μ B /f.u.), 967.75 kA/m (4.81 ± 0.04 μ B /f.u.), and 1003.52 kA/m (4.97 ± 0.04 μ B /f.u.) at 300 K, respectively. The soft ferromagnetic films possess coercivity of ∼ 15.92 kA/m (200 Oe) with a high effective anisotropy constant of ∼ 105 J/m3. Thermo-magnetization measurements yielded high Curie temperatures of 995 K, 1005 K, and 1123 K for films of thicknesses 320 nm, 780 nm, and 1400 nm, respectively. Tailoring the thickness from 320 to 1400 nm could be achieved by merely varying the electrodeposition time without appreciable departure from chemical stoichiometry or compromise in crystalline order or magnetic properties. This establishes a methodology to prepare high quality L2 1 ordered Co 2 FeSn films with a few hundred nanometers thickness by electrodeposition. Electrodeposited Co 2 FeSn films with high magnetic moment, high K e f f value, and high Curie temperature are potential candidates for fabricating nanomagnetic devices. [ABSTRACT FROM AUTHOR]

• First-principles calculations performed for XA and L2 1 phases across X 2 FeAl series. • The degree of d-d orbital hybridization drives magnetic and electronic properties. • Increasing X-site valence electron counts result in increased hybridization levels. • Orbital hybridization trends must be considered when predicting material properties. First-principles calculations are performed for full (L2 1) and inverse (XA) Heusler compounds X 2 FeAl, where X comprise a range of 3d (Sc, Ti, V, Cr), 4d (Y, Zr, Nb, Mo), and 5d (Hf, Ta, W) early and middle column transition metal elements. The formation energy difference between full and inverse phase and the degree of d-d orbital hybridization with increasing total valence electron count are shown to drive the magnetic properties (total and atomic magnetic moments, spin polarization) and electronic properties (band structure and projected density of states) of the material system. Specifically, X-site atomic magnetic moments take on increasingly Fe character with increasing valence electron count, in both full and inverse Heusler phases. This can be explained by changes on the degree of d-d hybridization between X- and Fe-site d orbitals. Synchronized energy shifts in the PDOS of the X- and Y-sites (Fe) across each of the full and inverse Heusler series provide us insight to controlling spin polarization via composition. This work demonstrates the need to holistically study the thermodynamic phase stability, magnetic moments, and spin polarization of Heusler alloys, in the framework of anti-site disorder and in a wider compositional context. The end goal of this study is to benefit the mapping of experimental results in search of a specific property, by providing a methodology for extrapolating properties based on experimental or theoretical results. [ABSTRACT FROM AUTHOR]

The structural, electronic, and magnetic properties of pure and Ti doped w-AlN were investigated using density functional theory with motivation to explore the properties of TiAl-VN complex in the matrix. A substitutional Ti dopant with cationic Al atom at nearest neighbor lattice site of VN was incorporated to form TiAl-VN complex in AlN. The electronic properties of the material revealed that TiAl-VN complex is energetically favorable in AlN and possessed a stable spin-triplet 3A2 ground state and doubly degenerate 3E excited state. A charge transfer from nitrogen vacancy towards Ti dopant was observed which was responsible to increase spin polarization in the electronic structure of AlN host material. Two intermediate band peaks due to hybridized Ti-3d states with N-2p states were seen in the forbidden region narrowing the bandgap of AlN. A local magnetic moment of 2.068 µB was found for the TiAl-VN complex in AlN that was reduced to 0.664 µB on doubling TiAl-VN complex. Hence, TiAl-VN complexes in AlN prefer to couple antiferromagnetically, switched by superexchange interactions between them. Our results show that TiAl-VN complex in AlN may be a robust candidate for applications in optoelectronics and antiferromagnetic spintronics devices. [ABSTRACT FROM AUTHOR]

In this manuscript, we investigate the effect of structural disorder on the physical properties of Pd-based Heusler alloys: PdCoMnAl, Pd2CoAl and Pd2MnAl using first-principles calculations. In fact, we are studying the structural properties of the equatorial quaternary Heusler alloy PdCoMnAl for three phases: type 1, type 2 and type 3, we have carried out this property to determine the most stable phases. The structural properties results show that the phase of type I, of this alloy is the most stable configuration. In addition, the band structures, and density of states calculations results show that this compound exhibits a half-metallic character with a 100% of spin polarization (SP) at the Fermi-level. The total magnetic moment of the Heusler compound is found to be 5.00 µB. Moreover, it is found that the Slater-Pauling is well described for this alloy. On the other hand, concerning total energy of the full Heusler Pd2YAl (Y = Co or Mn) alloys. It is found that such material in L21-type structure is always smaller than in the XA-type structure during the whole lattice variation variety and the L21-type structure is more energetically preferable for the both full alloys. In addition, the density of states at the Fermi level within the spin up and down states show the metallicity of these compounds. Our results show that the quaternary Heusler is a potential candidate for the spintronic applications. [ABSTRACT FROM AUTHOR]

Strain-mediated magnetism in 2D materials and dilute magnetic semiconductors hold multi-functional applications for future nano-electronics. Herein, First principles calculations are employed to study the influence of biaxial strain on the magnetic properties of Co-doped monolayer W S 2 . The non-magnetic W S 2 shows ferromagnetic signature upon Co doping due to spin polarization, which is further improved at low compressive (-2 %) and tensile (+2 %) strains. From the PDOS and spin density analysis, the opposite magnetic ordering is found to be favourable under the application of compressive and tensile strains. The double exchange interaction and p-d hybridization mechanisms make Co-doped W S 2 a potential host for magnetism. More importantly, the competition between exchange and crystal field splittings, i.e. ( Δ ex > Δ cfs ), of the Co-atom play pivotal roles in deciding the values of the magnetic moments under applied strain. Micromagnetic simulation reveals, the ferromagnetic behavior calculated from DFT exhibits low-field magnetic reversal (190 Oe). Moreover, the spins of Co-doped W S 2 are slightly tilted from the easy axis orientations showing slanted ferromagnetic hysteresis loop. The ferromagnetic nature of Co-doped W S 2 suppresses beyond ± 2 % strain, which is reflected in terms of decrease in the coercivity in the micromagnetic simulation. The understanding of low-field magnetic reversal and spin orientations in Co-doped W S 2 may pave the way for next-generation spintronics and straintronics applications. [ABSTRACT FROM AUTHOR]

The first-principle calculations of density functional theory were used to study the structural, electronic, magnetic, mechanic, and half-metallic behavior of Y2MnZ (Z = Al, Ga, In) within the spin generalized gradient approximation. These compounds can be experimentally synthesized due to their negative values of the calculated formation energies. Our calculations indicate that they are more stable in Cu2MnAl-type structure. The Hg2CuTi-type structure displays half-metallic characteristic with 100% spin polarization at the Fermi level. The value of calculated magnetic moment has an integer value of 2μB for Y2MnZ (Z = Al, Ga, In) in the Hg2CuTi-type structure which well matches with magnetic moments predicted from Slater–Pauling rule. Therefore, the Y2MnZ (Z = Al, Ga, In) in the Hg2CuTi-type structure is predicted to be a candidate for possible spintronics applications. [ABSTRACT FROM AUTHOR]

The Heusler type compounds (A2-x-yZy)MnZ (A = Ni, Pd, Pt; Z = Sb, Sn; x = 1, 0; and y = 0, antisite defects of Z atoms) are investigated to understand the induced magnetic properties. The structural phases C1b type half Heusler (x = 1, y = 0) compounds AMnZ and the corresponding L21 type full Heusler (x = y = 0) compounds A2MnZ and some disordered compounds (A1-yZy)MnZ and (A2-yZy)MnZ (y = 0.01, 0.05) were calculated using the Korringa-Kohn-Rostoker Green's function method. The antisite doping of 1% (5%) Sb retained (suppressed) the half metallicity at (Ni1-ySby)MnSb, whereas the other compounds were found to be gapless in both spin directions. The density of states at the Fermi level exhibits the explicit spin polarization in the compounds. The net magnetic moments of the compounds are closer in their values, wherein the manganese atom is responsible for the major contribution to the magnetic moments, which is much larger than the partial moment of the other constituents. The Curie temperature (TC) of the ordered ferromagnetic compounds was estimated using the mean-field approximation. The TC higher than the room temperature was found for the ordered compounds, except for the cases of Pt2MnSb and Pt2MnSn. No literature value of TC has been reported yet for these two compounds. Calculated spin moments and TC agree well with the experimental results, where available. [ABSTRACT FROM AUTHOR]

The requirement of the continuous reduction of the device size prompts the development of the low-dimensional materials. The structural, electronic, and magnetic properties of CoS2-FeS2 interface thin films are studied by first principles calculations considering spin polarization. The low-dimensional SS-Fe-terminated and SS-SS-terminated CoS2-FeS2 interfacial thin films are half-metallic and therefore are potential materials to be applied in spintronics. Both the partial density of states and Bader charge states of atoms are more affected by the surface effect than by the interface effect for all the interfacial thin films. The magnetic moment of the CoS2-FeS2 interface thin films is mainly distributed on Co atoms on the CoS2 side, and the changes of magnetic moment of the atoms near the surface are more obvious than those near the interface. The magnetic charge density of Fe atoms in the metallic interfacial thin films is more obvious than that in the half-metallic interface films. The individual CoS2 (FeS2) film and the SiO2 substrate affect the property of the corresponding CoS2-FeS2 interfacial thin film. [ABSTRACT FROM AUTHOR]

With the intention to reveal the effect of the substitution, Ti-doped InSb alloy, we accomplished a first-principles prediction within the FPLAPW+lo method. We used GGA-PBEsol scheme attached with the improved TB-mBJ approach to predict structural, electronic, and magnetic properties of In1-xTixSb with concentration x = 0, 0.125, 0.25, 0.50, 0.75, 0.875, and 1. Our lattice parameters are found in favorable agreement with the available theoretical and experimental data. The calculation shows that all structures are energetically stable. The substitutional doping transforms the ionic character of the InSb compound in half-metallic ferromagnetic comportment for concentration x = 0, 0.125, 0.25, and 0.50, with a spin polarization of 100% at the Fermi level, and metallic nature for In0.25Ti0.75Sb and In0.125Ti0.875Sb. The total magnetic moments are also estimated at about 1 μB. In0.875Ti0.125Sb, In0.75Ti0.25Sb, and In0.50Ti0.50Sb have half-metallic ferromagnets comportment and they can be upcoming applicants for spintronics applications. [ABSTRACT FROM AUTHOR]