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In the present work, we investigate the electronic structure and magnetism of InN nanoribbon doped with 3d Mn atoms in different positions by first-principle density functional calculations. The structural stability is described by using the calculated total energy of the doped nanoribbons including the antiferromagnetic (AFM) and the ferromagnetic (FM) coupled states. Our calculations show that the ground state is ferromagnetic regardless of the position of Mn atoms. The dependence of bandgap and spin polarization on Mn positions makes it possible to control the electronic properties by choosing the impurity position and applying these structures in nanoelectronics and spintronics. [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]

In this work, the electronic and magnetic features of the Sc2MnSi bulk, surfaces, and the interface with the semiconductor CdTe (111) were thoroughly researched using the first-principles calculations. The Sc2MnSi alloy with equilibrium lattice constant of 6.34 Å shows half-metallic (HM) property. This alloy exhibits an energy gap and a HM gap of 0.54 and 0.12 eV, respectively. The density of states results confirm the existence of the half-metallicity property for the Sc2MnSi component at SiSc(2)-(001), Sc(2)-, and Si-(111) surfaces while this property is not revealed at Sc(1)-, Mn-terminated (111), Sc(1)Mn-terminated (001), and Sc2MnSi (110) surfaces for the same component. In addition, in the case of Sc2MnSi/CdTe interface, it is noted that Cd-Si connection does not reveal the half-metallicity feature, while the Si-Te shape exhibits a 100% spin polarization, thus preserving the half-metallicity. Furthermore, the Si-Te shape is more stable than the others, according to the interfacial adhesion energy. [ABSTRACT FROM AUTHOR]

The structural parameters, exchange splittings, half-metallic property, electronic features and magnetic performances of Ba1−xCrxS materials were determined by utilizing the computational methods of density functional theory. The localized magnetic spins in the Ba1−xCrxS result from the effect of the hole carriers caused by the d shells of Cr atom, hybridizing with p levels of S atom. The ferromagnetism is mostly endorsed by the exchange splitting owing to its large contribution than that of the crystal field. The Ba1−xCrxS (x = 0.25), Ba1−xCrxS (x = 0.5)and Ba1−xCrxS (x = 0.75) materials have half-metallic characteristic with ferromagnetic state, where their electronic structures demonstrate spin polarizations of 100% with half-gaps of 0.815, 0.912 and 0.72 eV, respectively. Therefore, Ba1−xCrxS systems have better magneto-electronic performances, making them appropriate half-metallic materials for spin-injection applications for spintronics. [ABSTRACT FROM AUTHOR]

Based on the first-principle calculations, the electronic structure and magnetic properties of MgO materials (bulk doped with intrinsic defects, transition metal elements Co and Ni; surface doped with non-metallic elements C and N, in addition to Co and Ni) have been systematically investigated. The calculation results show that the oxygen vacancy (VO) in the MgO bulk material cannot make the system spin polarization. When magnesium vacancy (VMg) is introduced, a local magnetic moment of 1.31 μB will be produced, and the magnetic coupling between magnesium vacancies at each distance is ferromagnetic; isolated Co and Ni can produce high-spin states of S = 3/2 and 1, respectively. However, Co–Co are mainly coupled antiferromagnetically at different distances, and the magnetic coupling of Ni–Ni will produce the oscillation phenomenon between FM and AFM states. MgO (001) surface studies reveal that the spin polarization of 2p orbitals of isolated C and N may produce local magnetic states of 0.96 μB and 0.59 μB, respectively. C–C and N–N at different distances are both mainly coupled ferromagnetically. Although one single Co atom will produce a magnetic moment of 1.00 μB on the surface, Co–Co at different distances are mainly antiferromagnetic coupling, while the magnetism is not produced by Ni. Our research is beneficial to the development of spintronics. [ABSTRACT FROM AUTHOR]

We present a combined investigation of the electronic structure of bulk arc-melted full-Heusler Co 2 - x Fe 1 + x Si (x = 0, 0.5, 1) and CoFeSi alloys using density functional theory and ultrasoft X-ray emission spectroscopy. We perform first-principles calculations of the spin-polarized total and partial density of states for the Co and Fe 3d (s, p) as well as for the Si 3s (p, d) orbitals. It is demonstrated that only Co 2 FeSi alloy exhibits a half-metallic behavior. However, the inverse CoFe 2 Si alloy shows pseudogap and high spin polarization at the Fermi level. We carry out ultrasoft X-ray emission Si L 2 , 3 measurements, which provide the information about the local partial density of states of Si 3s and 3d orbitals in the valence band localized on Si atoms. We compare the measured spectra with our theoretical calculations and discuss them in terms of the contribution of s and d-electrons to the bonding. The Si and transition-metals sd and dd bonding formation is shown in the Co 2 - x Fe 1 + x Si and CoFeSi alloys. The high spin polarization values, along with the extremely high Curie temperature, make these compounds potential candidates for spintronic applications. [ABSTRACT FROM AUTHOR]

Density functional theory-based investigation of the electronic, magnetic, and optical characteristics in pure and ytterbium (Yb) doped ZnO has been carried out by the plane-wave pseudopotential technique with generalized gradient approximation. The calculated lattice parameters and band gap of pure ZnO are in good agreement with the experimental results. The energy band gap decreases with increasing Yb concentration. The Fermi level moves upward into the conduction band after doping with Yb, which shows the properties of an n-type semiconductor. New defects were created in the band-gap near the conduction band attributed to the Yb-4f states. The magnetic properties of ZnO were found to be affected by Yb doping; ferromagnetic property was observed for 4.17% Yb due to spin polarization of Yb-4f electrons. The calculated optical properties imply that Yb doped causes a blue shift of the absorption peaks, significantly enhances the absorption of the visible light, and the blue shift of the reflectivity spectrum was observed. Besides, a better transmittance of approximately 88% was observed for 4.17% Yb doped ZnO system. The refractive index and the extinction coefficient were observed to decrease as the Yb dopant concentration increased. As a result, we believe that our findings will be useful in understanding the doping impact in ZnO and will motivate further theoretical research. [ABSTRACT FROM AUTHOR]

The emergence of ferromagnetism in two-dimensional van der Waals materials has aroused broad interest. However, the ferromagnetic instability has been a problem remained. In this work, by using the first-principles calculations, we identified the critical ranges of strain and doping for the bilayer Cr2Ge2Te6 within which the ferromagnetic stability can be enhanced. Beyond the critical range, the tensile strain can induce the phase transition from the ferromagnetic to the antiferromagnetic, and the direction of magnetic easy axis can be converted from out-of-plane to in-plane due to the increase of compressive strain, or electrostatic doping. We also predicted an electron doping range, within which the ferromagnetism can be enhanced, while the ferromagnetic stability was maintained. Moreover, we found that the compressive strain can reverse the spin polarization of electrons at the conduction band minimum, so that two categories of half-metal can be induced by controlling electrostatic doping in the bilayer Cr2Ge2Te6. These results should shed a light on achieving ferromagnetic stability for low-dimensional materials. [ABSTRACT FROM AUTHOR]

High-spin-polarized materials are the promising candidates in spintronic devices. Here, the spin-polarized electronic structure, magnetism, and mechanical properties of Ti2.25Co0.75Si and Ti2.25Co0.75Si0.5X0.5 (X = As and Sb) Heusler alloys were calculated by first-principles calculations. The results show that Ti2.25Co0.75Si and Ti2.25Co0.75Si0.5Sb0.5 are ferromagnetic half-metals with 100% spin polarization, while Ti2.25Co0.75Si0.5As0.5 is a zero-gap half-metal. The complete spin-polarized characteristics of Ti2.25Co0.75Si and Ti2.25Co0.75Si0.5X0.5 are confirmed to be robust to hydrostatic and uniaxial strains. The results of the elastic constants and phonon spectra demonstrate the mechanical and dynamic stabilities of Ti2.25Co0.75Si and Ti2.25Co0.75Si0.5X0.5 alloys. Furthermore, the magnetic anisotropy results show that the easy magnetic axis of Ti2.25Co0.75Si can be tuned from the in-plane direction to the out-of-plane one under the uniaxial strains. Ti2.25Co0.75Si and Ti2.25Co0.75Si0.5X0.5 (X = As and Sb) alloys are promising candidates for the potential application in spintronic devices. [ABSTRACT FROM AUTHOR]

The electronic structure and spin polarization properties of transition-metal (TM) doped monolayer MoSeTe are studied by using the first-principles calculations based on density functional theory. The calculated results demonstrate that V, Mn, Fe, Co and Ni doped MoSeTe monolayer show spin polarization with large magnetic moments. There exist strong p-d hybridization between the doped TM atoms and MoSeTe, so new spin impurity states appear around the Fermi level after TM doping, which induces the spin polarization of the systems. The calculated density of states, spin density distributions as well as the charge transfer indicate that the spin polarization caused by Co dopant is the largest one. This work suggests that TM atom doped MoSeTe has considerable application prospects in the research field of electronics and spintronics. [ABSTRACT FROM AUTHOR]

In this study, we have employed the first-principle methods based on spin-polarized density functional theory to investigate the structural parameters, the electronic structures, and the half-metallic ferromagnetic behavior of chromium (Cr)-doped barium selenide (BaSe) such as Ba1 − xCrxSe at concentrations x = 0.25, 0.5, and 0.75. The exchange and correlation potential is described by the generalized gradient approximation of Wu and Cohen (GGA-WC). The calculated structural parameters of BaSe are in good agreement with theoretical data. Our findings reveal that the p-d exchange coupling is ferromagnetic for Ba0.75Cr0.25Se and Ba0.5Cr0.5S, but it becomes anti-ferromagnetic for Ba0.25Cr0.75S. The electronic structures exhibit that the Ba1 − xCrxSe materials for all concentrations are half-metallic ferromagnets with spin polarization of 100% and total magnetic moment per Cr atom of 4 μB. Therefore, the Ba1 − xCrxSe compounds are suitable candidates for possible spintronics applications. [ABSTRACT FROM AUTHOR]

The first-principle methods of density functional theory were used to investigate the doping effect of 3d chromium (Cr) impurities on the electronic properties and the ferromagnetic arrangement of (BaO) barium oxide such as Ba1−xCrxO compounds at concentrations x = 0.25, 0.5, and 0.75. The p–d exchange coupling between 2p states of oxygen (O) and 3d (Cr) partially filled levels induces magnetism in the Ba1−xCrxO compounds. The majority- and minority-spin states exhibit respectively metallic and semiconducting features, leading to a half-metallic (HM) character with 100% spin polarization for all concentrations. The Ba0.75Cr0.25O, Ba0.5Cr0.5O, and Ba0.25Cr0.75O compounds have integral total magnetic moments of 4 μB per Cr atom with HM gaps of 0.055, 0.218, and 0.308 eV, respectively. These behaviors form accurate half-metallic ferromagnets and make Ba1−xCrxO as potential materials for possible spintronics applications. [ABSTRACT FROM AUTHOR]

We perform a first principle calculation on different magnetic configurations of PuH3 system to describe this system at electronic level using local density approximation and generalized gradient approximation (GGA) within the framework of density functional theory inclusion of spin polarization (SP), on-site Coulomb repulsion U and spin-orbit coupling (SOC) effect, which are essential for strongly correlated system. The results indicate that Coulomb repulsion and SOC effects are necessary to correctly capture the electronic, magnetic and lattice properties of PuH3, however, SP has a negligible effect on lattice parameter calculations. SP + GGA + U + SOC (5.3420 Å) and GGA + U + SOC calculations (5.3438 Å) on ferromagnetic order (FM) are in good agreement with experimental value (5.34 Å) and full-potential linearized augmented plane wave calculation (5.343 Å). FM magnetic order and total magnetic moment for SP + GGA + U + SOC method are also consistent with experimental and calculation results. [ABSTRACT FROM AUTHOR]

We report first-principles calculations of the elastic properties, electronic structure and magnetic behavior performed over the Ba2NiMoO6 double perovskite. Calculations are carried out through the full-potential linear augmented plane-wave method within the framework of the Density Functional Theory (DFT) with exchange and correlation effects in the Generalized Gradient and Local Density Approximations, including spin polarization. The elastic properties calculated are bulk modulus (B), the elastic constants (C11, C12 and C44), the Zener anisotropy factor (A), the isotropic shear modulus (G), the Young modulus (Y) and the Poisson ratio (υ). Structural parameters, total energies and cohesive properties of the perovskite are studied by means of minimization of internal parameters with the Murnaghan equation, where the structural parameters are in good agreement with experimental data. Furthermore, we have explored different antiferromagnetic configurations in order to describe the magnetic ground state of this compound. The pressure and temperature dependence of specific heat, thermal expansion coefficient, Debye temperature and Grüneisen parameter were calculated by DFT from the state equation using the quasi-harmonic model of Debye. A specific heat behavior CV ≈ CP was found at temperatures below T = 400 K, with Dulong-Petit limit values, which is higher than those, reported for simple perovskites. [ABSTRACT FROM AUTHOR]

In this work, the Fe-based single atomic chains are designed in the semiconductive CoFeTiAl quaternary Heusler matrix by substituting Ti, Al, or Ti-Al with Fe in [001] crystallographic direction. We have investigated the electronic structures and magnetic characteristics of the Fe-based supercells by using the first-principles calculations. Our results show that all the three kinds of single atomic chains Fe-Al, Fe-Ti, and Fe-Fe atomic chains show a half-metallicity with 100 % spin polarization. A conductive nanopillar is formed and dilutedly distributed in CoFeTiAl matrix. The width of the nanopillar is about half of the lattice parameter, and the length of it will be adjustable. It would be an ideal method to design the new direct-current-magnetic memory device. [ABSTRACT FROM AUTHOR]

The objective of this work is to predict the structural, electronic and magnetic properties of Mg Cr S ( x = 0, 0.25, 0.50, 0.75 and 1) compound in the zinc blende ferromagnetic phase using the first principal approach. The structural properties are performed using the generalized gradient approximation developed by Perdew-Burk-Ernzerhof (PBE-GGA). However, the electronic and magnetic properties have been performed using the modified Becke-Johnson potential combined with the LDA correlation (mBJLDA) which provides better description of electronic properties than PBE-GGA. The results show that this compound exhibits a half-metallic ferromagnetic character with 100 % spin polarization at the Fermi level. For all Cr concentrations (0.25, 0.50, 0.75 and 1), the total magnetic momentum is equal to 4 μ , and there is a small local magnetic moment on the Mg and S sites. Furthermore the local magnetic moments of Cr atom reduce from their free space charge value. [ABSTRACT FROM AUTHOR]

Based on first-principles calculation method, the electronic structure and magnetic interactions of Ti-doped β-GaO and Ti-V-co-doped in β-GaO have been investigated. The calculated results indicate that Ti atom tends to substitute the Ga atom at the octahedral coordinated site and the doped system prefers spin-polarized state. The magnetic moment of Ti-doped β-GaO is 0.546 μ per cell, which mainly arises from Ti 0.48 μ . The origin of ferromagnetism in Ti-doped β-GaO can be explained by a double-exchange mechanism. When a V defect is introduced into Ti-doped β-GaO, the magnetic moment increases and the ferromagnetic coupling between Ti atoms is strengthened. The influence of V defect on ferromagnetic properties of Ti-doped β-GaO comes from the enhancement of hybridization between Ti-3 d and O-2 p states. [ABSTRACT FROM AUTHOR]

The electronic structure and the optical properties of the HoCoSi and ErNiSi compounds are studied. Spin-polarized band calculations are performed in the local electron density approximation corrected for the strong electron-electron interactions in the 4 f shell of a rare-earth ion (LSDA + U method [11]). The optical constants are measured by ellipsometry in a wide wavelength range, and the frequency dependences of a number of spectral parameters are determined. The calculated densities of states are used to interpret the structural features of the interband optical conductivities of the intermetallic compounds. [ABSTRACT FROM AUTHOR]

Mn -based Heusler compounds exhibit different types of anti-site disorder. The electronic structure and magnetism of Heusler alloys MnRhZ (Z = Si, Ge, and Sn) have been studied by first-principle calculations. MnRhSi and MnRhGe are ordinary half-metallic ferrimagnetic metals at equilibrium lattice constants, with a magnetic spin moments obeys to the Slater-Pauling rule and spin polarization of 100 % at the Fermi energy. The tetragonal phase transformation is studied for MnRhSn. The total magnetic moment of MnRhSn in the tetragonal structure is higher compared to the other materials, which results in a large Δ M between the saturation moments of tetragonal and a cubic. The tetragonal MnRhSn predicted to a high spin polarization ratio of 93 %. These properties of these materials are particularly interesting due to their perpendicular magnetic anisotropy (PMA), which was realized in thin films opening the door for application in STT magnetic random access memories (STT-MRAMs) [ABSTRACT FROM AUTHOR]

The electronic structure of the neutral vacancy in diamond is investigated by using a periodic approach (supercells containing 32, 64 and 128 atoms have been considered), the Hartree–Fock (HF), pure DFT (LDA, PBE), global (B3LYP and PBE0) and range-separated (HSE06) "hybrid" functionals, and a local basis set as implemented in the CRYSTAL14 code. LDA and GGA provide metallic solutions for the three possible spin states (characterized by S z = 0 , 1 , 2 ), whereas hybrids and HF, thanks to the "exact" exchange, which plays such a crucial role in the present case, provide well-localized defect states in the band gap of the insulating system. As a consequence of the metallic solution, for the S z = 0 and 1 states, the spin polarization tends to disappear when pure DFT is used, while with HF and hybrids the uncoupled electrons remain strongly localized on the first nearest neighbors, as documented by the spin density maps. The relative stability between the three spin states is 0 < 1 < 2 for HF and hybrids, with a small difference between the first two (about 5 mE h in the case of hybrids and HF) and a much larger difference between S z = 1 and 2 (about 50 mE h for hybrids, 28 for HF). As regards PBE and LDA results, the stability order between S z = 0 and 1 is reversed, and S z = 2 is less stable than S z = 0 by only 8–10 mE h . The defect crystalline orbitals are classified by symmetry and identified in the band structure with respect to the valence and conducting electrons. The formation energy of the vacancy, evaluated with six different functionals, is close to 7 eV for three of them (7.00 HSE06, 7.05 LDA, 7.11 PBE0), slightly smaller in B3LYP (6.74) and PBE (6.56). Cluster calculations ( C 35 H 36 and C 455 H 196 ) are also performed in comparison with the supercell results and for obtaining, with the smaller one, a coupled-cluster estimate of the energy differences between the three spin states that turn out to be close to the ones obtained with hybrids. [ABSTRACT FROM AUTHOR]

Self-consistent ab initio calculations, based on the density functional theory approach and using the full potential linear augmented plane wave method, are performed to investigate both electronic and magnetic properties of the MnBi compounds. Polarized spin and spin-orbit coupling are included in calculations within the framework of the ferromagnetic state between two adjacent Mn atoms. The magnetic moment considered to lie along (001) axes are computed. The obtained data from ab initio calculations are used as input for the high-temperature series expansions calculations to compute other magnetic parameters. The exchange interactions between the magnetic atoms Mn-Mn in MnBi are given using the mean field theory. The high-temperature series expansions of the Ising model magnetic susceptibility is given up to the tenth order series in x = J(Mn-Mn) / k T. The Curie temperature, T, is obtained using high-temperature series expansions of the magnetic susceptibility series combined with the Padé approximant method. The critical exponent γ associated with the magnetic susceptibility is deduced as well. [ABSTRACT FROM AUTHOR]

The electronic structures of LaNiO, where additional interstitial oxygens are forming stripes along (1,1,0), are presented. Spin-polarized calculations show that ferromagnetism on Ni sites is reduced near the stripes and enhanced far from the stripes. Totally, the magnetic moment becomes reduced because of interstitial oxygens. It is suggested that the oxygen interstitial concentration in oxygen-rich domains in nickelates suppress magnetism and give multiband metallic domains. [ABSTRACT FROM AUTHOR]

A first-principles study on the electronic structure and magnetic properties of the RuZrSb Heusler compound has been performed by using the self-consistent full-potential linearized augmented plane wave (FPLAPW) method. It is found that the AlCuMn-type structure exhibits half-metallic ferrimagnetism and is preferable energywise than the CuHgTi-type structure. The total spin magnetic moment is based on mainly the Ru atoms and obeys the Slater-Pauling rule. The calculated total magnetic moment of RuZrSb is −1.0 μ at the equilibrium lattice constant 6.497 Å for the AlCuMn-type structure. The spin-down electrons are metallic, but the spin-up bands are semiconductor with a gap of 0.388 eV, and the spin-flip gap is 0.313 eV. The AlCuMn-type RuZrSb Heusler compound keeps a 100 % of spin polarization for lattice constants ranging between 6.40 and 6.53 Å. The Curie temperature is estimated to be 322.7 K in the mean field approximation (MFA). [ABSTRACT FROM AUTHOR]

A first-principles study of the electronic structure and magnetic properties of the Heusler compound Mn NbAl has been performed. The calculations have been performed by using the self-consistent full-potential linearized augmented plane wave (FPLAPW) method. It is found that the AlCu Mn-type structure is preferable energy wise than the CuHg Ti-type structure and exhibits half-metallic ferrimagnetism. The calculated total magnetic moment of Mn NbAl is 2 μ at the equilibrium lattice constant of 6.005 Å for the AlCu Mn-type structure. The total spin magnetic moment obeys the Slater-Pauling rule and is based on mainly the Mn atoms. The spin-down electrons are metallic, but the spin-up bands are semiconductor with a gap of 0.37 eV, and the spin-flip gap is of 0.09 eV. The AlCu Mn-type Mn NbAl full-Heusler compound keeps 100 % of spin polarization for lattice constants ranging between 5.93 and 6.20 Å. The Curie temperature is estimated to be 994 K in the mean field approximation (MFA). [ABSTRACT FROM AUTHOR]

The electronic properties and ferromagnetic coupling interactions of Mg-doped cubic boron nitride (BN) have been investigated by using first-principles calculation method. The calculated results show that Mg-doped BN takes ferromagnetic ground state with magnetic moment of 0.565 μ which mainly comes from the unpaired 2 p electron of N atoms around the Mg dopant. The magnetic coupling between Mg dopants induced moments is long-ranged. It also was found that the Mg-doped BN system has high spin polarization near the Fermi level. [ABSTRACT FROM AUTHOR]

The article discusses the research on the first-principles calculations to determine the electronic, magnetic, and structural properties of ferromagnetic nanowires that was encapsulated inside a silicon carbide nanotubes (SiCNTs). Topics discussed include the changes on initial shapes of ferromagnetic for nanotube and nanowire, the magnetism of ferromagnetic nanowires, and the fermi level of spin polarization. Also mentioned is the use of density functional theory on the structure of SiCNTs.

The electronic structure of the ground and low-energy excited states of the CoFeSi Heusler alloy is investigated by the methods of X-ray absorption spectroscopy (XAS) and resonant X-ray photoelectron spectroscopy (RXPS). The orbital and spin magnetic moments of the iron and cobalt atoms are determined in a 0.05 T magnetic field. A comparative analysis is given of two amplifier channels of the valence band photoemission at the resonant excitation of the 2 p level: elastic and Auger electron emission. A decrease in the magnetic moment of the atom leads to a qualitative change in the resonant photoemission spectrum. The valence electron shake-up at a sudden appearance of a 2 p core photohole on the iron atoms leads to multiple formations of low-energy electron-hole pairs and gives rise to continuous losses in the XPS and XAS spectra. Shake-up in the cobalt atoms with great probability gives rise to one electron-hole pair with an energy of 4 eV, which is manifested as a satellite band in the above mentioned spectra. The mentioned feautures are closely related to semimetal ferromagnetism. [ABSTRACT FROM AUTHOR]

Spin-polarization calculations of the electronic structure of intermetallic compounds DyNiCu ( x = 0, 1, 2) are performed in the local spin density approximation with strong electron correlations in the 4 f shell of a rare-earth ion taken into account (the LSDA + U). Spectral properties of these materials are studied by the optical ellipsometry method in the wavelength range of 0.22-16 μm. It is established that the optical absorption spectra are significantly modified upon partial substitution of nickel by copper atoms. The experimental dispersion dependences of optical conductivity in the region of interband light absorption are interpreted on the basis of calculations of electronic state densities. [ABSTRACT FROM AUTHOR]

We analyze the electronic structure of interfaces between two-, four- and six-layer Gd(0001) and monolayer MoS2 by first-principles calculations. Strong chemical bonds shift the Fermi energy of MoS2 upwards into the conduction band. At the surface and interface the Gd f states shift to lower energy and new surface/ interface Gd d states appear at the Fermi energy, which are strongly hybridized with the Mo 4d states and thus lead to a high spin-polarization (ferromagnetically ordered Mo magnetic moments of 0.15 μB). Gd therefore is an interesting candidate for spin injection into monolayer MoS2. [ABSTRACT FROM AUTHOR]

We have performed the first-principles calculations on the structural, electronic, and magnetic properties of 3d transition-metal nanowires (TMNWs), Fe, Co, and Ni, encapsulated inside GaN nanotubes (GaNNTs). The results show that, all three types of the TMNW encapsulated inside the narrower (6,6) and broader (8,8) GaNNTs are both exothermic. The spin polarization and magnetic moment of the TMNW@(8,8) systems are larger than those of the TMNW@(6,6) systems due to more weak restriction of the broader (8,8) GaNNT, but those of these two combined systems are smaller than those of the corresponding freestanding TMNW. Our results reveal that either the TMNW@(6,6) or TMNW@(8,8) systems have high spin polarization and magnetic moment and stably exist in atmosphere for long time and thus can be expected to have potential applications in building nanodevices. [ABSTRACT FROM AUTHOR]

A kind of magnetic superatom is designed by doping transition metal element into Na clusters. Their electronic structure and spin-polarized transport properties are investigated using the first principles method. Our calculation shows that electrode materials have notable influence on the superatoms' geometrical stability. Lithium lead is a good choice. Among all the superatoms, TiNa and NiNa give the highest transmission spin polarization (TSP), for negative and positive values, respectively. Relation between TSP and the magnetic moment of isolated superatom may lead to some promising designs in molecular spintronics devices. [ABSTRACT FROM AUTHOR]

In this paper experimentally measured optical properties of intermetallic ternary compounds DyRhSn and HoRhSn are reported together with the spin-polarized calculations of the electronic structure within DFT+U method, accounting for electronic correlation effects in the 4f shell of Dy and Ho. A number of spectral and electronic characteristics are determined. The performed calculations allow one to qualitatively interpret the energy dependencies of the interband optical conductivity extracted from experimental ellipsometry measurements. [ABSTRACT FROM AUTHOR]