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Highlights • Spin-polarized transport through topologically superconducting wire is studied. • Current-switch effect mediated by Majorana bound states (MBSs) is found. • The effect is based on the dependence of MBS spin polarization on magnetic-field orientation. • The direction of spin-polarized current can be changed by magnetic gate. • The observed current-switch effect allows electrical detection of the MBSs. Abstract We present the study of transport properties of a superconducting wire with strong Rashba spin-orbit coupling for different orientations of an external magnetic field. Using the nonequilibrium Green’s functions in the tight-binding approach the crucial impact of the relative alignment of lead magnetization and the Majorana bound state (MBS) spin polarization on the low-bias conductance and shot noise is presented. Depending on this factor the transport regime can effectively vary from symmetric to extremely asymmetric. In the last situation the suppression of MBS-assisted conductance results in current-switch effect allowing the electrical detection of the Majorana fermions. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The full Heusler alloy (Fe 2 CoSn) nanowires are formed using AC electrodeposition in AAO templates. • The SEM images have confirmed the average diameter and length of nanowires 40–60 nm and 15 μm respectively. • The M-H loops show the variation of coercivity and saturation magnetization with respect to deposition potential. • The half-metallicity, band gap and 100% spin polarization was also confirmed using density functional theory (DFT). Abstract Fe 2 CoSn Heusler alloy nanowires (NWs) were synthesized for the first time through alternating current (A.C) electrodeposition due to its manufacturing and size tailoring ease. To approach our desired goal, deposition potential was used to control the alloy composition of Fe, Co and Sn contents as it was almost inversely proportional to the composition ratio of Sn and (Fe, Co). The effects of deposition potential on morphology, chemical composition, crystal structure and electric/magnetic properties were investigated. According to the scanning electron microscopy (SEM) micrographs, the Fe 2 CoSn NWs exhibited diameter of about 40–60 nm range and the length existing in the range of 15 µm. X-ray diffraction (XRD) patterns reveal that two types of reflection were observed i.e. fundamental (A2-type crystal structure) and super-lattice (L2 1 crystal structure) reflection. Almost 35 nm was the average grain size calculated through XRD technique using full width half maximum (FWHM). The composition of Fe 2 CoSn nanowires has been confirmed by using EDX analysis, whereas surface chemistry of Heusler alloy (Fe 2 CoSn) NWs was examined through FTIR. Magnetic measurement indicated that Fe 2 CoSn Heusler alloy was ferromagnetic at room temperature with a maximum coercivity of 484 Oe at 17 V. Two probe (I-V) curve showed non-ohmic character and Hall measurement (Four probe) revealed the inverse relation between resistivity (ρ), mobility (µ) and followed excellent transport as well as spin dependent properties of Heusler alloy (Fe 2 CoSn) NWs. Half metallicity in (Fe 2 CoSn) Heusler alloy NWs was confirmed by full potential lineralized augmented plane wave methods (FP-LAPW) within density functional theory (DFT) in detail. These results revealed that Heusler alloy (Fe 2 CoSn) NWs have wide range of multifunctional properties such as combination of magnetism and exceptional transport properties in spintronic devices. [ABSTRACT FROM AUTHOR]

Highlights • Surface antiferromagnetism of the Cr(0 0 1) c(2 × 2) surface. • Quantitative determination of the antiferromagnetic coupling angles. • New spin quantization axes along the [1 1 0] of Cr(0 0 1). Abstract We present spin-polarized scanning tunneling microscopy results for 8 micrometer thick, chromium (0 0 1)-oriented thin films deposited using molecular beam epitaxy on MgO(0 0 1) substrates, achieving a smooth, atomically-stepped staircase morphology. The c(2 × 2) surface structure of the Cr(0 0 1) surface was found via atomically-resolved scanning tunneling microscopy images and dI/dV spectroscopy. A practical method of interpreting spin-polarized scanning tunneling microscopy dI/dV images was developed and applied to the c(2 × 2) Cr(0 0 1) surface structure. A 180° spin reversal between atomic layers, characteristic of a topological, layer-wise antiferromagnetic spin structure, was quantitatively verified. In addition, the spin anisotropy directions for 3 different antiferromagnetic, atomic staircase domains occurring on the c(2 × 2) surface were quantitatively determined to coincide with the [1 0 0], [0 1 0], and [1 1 0] crystallographic axes of chromium. [ABSTRACT FROM AUTHOR]

Highlights • A spin current generator in a single molecular magnet is realized. • The spin-related currents are studied by Hubbard operator Green’s function method. • The system can generate spin-polarized current or pure spin current. • Two configurations of spin bias are considered and they show different features. Abstract In this paper we study the spin- and charge-transport behaviors of a single molecular magnet (SMM) coupled to external reservoirs with spin-dependent chemical potentials. By using the Hubbard operator Green’s function method, we show that in the limit of a pinned macrospin the SMM can serve as an effective spin current filter or generator. Two configurations of spin bias are considered. For SMM coupled with symmetric dipolar spin bias, the system can generate spin-polarized current and pure spin current by adjusting the relative magnitude of spin bias and Coulomb interaction. It originates from the competition of two spin-opposite transport channels. Also due to this competition, one can observe a negative differential spin conductance. For SMM coupled with asymmetric dipolar spin bias, the system can only generate spin-polarized currents. The SMM as a spin current generator shows features different from the usual quantum dot system and these features can be useful in molecular spintronics. [ABSTRACT FROM AUTHOR]

Abstract The spin-phonon interaction is the dominant process for spin relaxation in Si, and as thermal transport in Si is dominated by phonons, one would expect spin polarization to influence Si's thermal conductivity. Here we report the experimental evidence of just such a coupling. We have performed concurrent measurements of spin, charge, and phonon transport in p-doped Si across a wide range of temperatures. In an experimental system of a free-standing 2 μm p-Si beam coated on one side with a thin (25 nm) ferromagnetic spin injection layer, we use the self-heating 3ω method to measure changes in electrical and thermal conductivity under the influence of a magnetic field. These magneto-thermal transport measurements reveal signatures in the variation of electrical and thermal transport that are consistent with spin-phonon interaction. Raman spectroscopy measurements and first principle's calculations support that these variations are due to spin-phonon interaction. Spin polarization leads to softening of phonon modes, a reduction in the group velocity of acoustic modes, and a subsequent decrease in thermal conductivity at room temperature. Moreover, magneto-thermal transport measurements as a function of temperature indicate a change in the spin-phonon relaxation behavior low temperature. Highlights • We observe spin-phonon interactions mediated magneto-thermal transport behavior in Si. • The transport measurements are supported by Raman spectroscopy and simulations results. • The magneto thermal transport measurements are carried out using self-heating 3 omega method. [ABSTRACT FROM AUTHOR]

The electrical approach is favored over the conventional magnetic approach for its low energy consumption and continuously variable control of spin polarization. Inspired by the recently reported PC 3 monolayer, we investigate its spin-dependent electron transmission characteristics through the first-principles calculations. The results show that the transmission peaks with opposite spin directions at the Fermi level have precisely opposite responses to the gate voltage, which leads to the system being able to alter between spin-polarized and unpolarized states, and as well as achieving any ratio between − 100 % and 100 % for spin-up and spin-down electrons. Notably, this regulation is also reversible and mirror-symmetric. Further research demonstrates that the crux lies in the particular transmission peak contributed by the edge sp 2 -hybridized C atoms. This study sheds new light on the potential of PC 3 as a novel nanoelectronic material for spintronics applications, suggesting that it can be used to create bipolar spin filters with tunable filtering effects. • PC 3 NR is a dual-spin filter capable of producing high spin-polarized currents. • Spin polarization transitions monotonically from − 100 % to 100 %, realizing arbitrary spin-up and down electron ratios. • The transmission peaks with opposite spin directions at E F have precisely opposite responses to the gate voltage. [ABSTRACT FROM AUTHOR]

The g-C 6 N 6 is a semiconductor material, the effect of this material used in electronic and microelectronic devices is far from reaching the expected effect. To improve the overall performance of g-C 6 N 6 , this study decided to cut g-C 6 N 6 for nanoribbons. It was found that g-C 6 N 6 nanoribbons could not be directly used in electronic devices and microelectronic devices through first principles calculation. In order to change its properties, it was decided to adsorb two different transition metal atoms Fe and Mn in the g-C 6 N 6 nanoribbons, respectively. The results show that g-C 6 N 6 nanoribbons have magnetic properties after adsorbing transition metal atoms, and the two structures have spin polarization phenomena after adsorption of Fe and Mn atoms. Their energy band, density of states (DOS) and the charge density after the adsorption of transition metal atoms were analyzed. The results show that g-C 6 N 6 nanoribbons becomes an indirect narrow band gap semiconductor by adsorbing different transition metal atoms, which improves the performance of g-C 6 N 6 nanoribbons. Through computational molecular dynamics simulation, g-C 6 N 6 nanoribbons can exist stably in a real environment. Our research provides theoretical support for the application of such materials in spintronics devices and optoelectronic devices. • The g-C6N6 nanoribbons generate magnetism by adsorbing transition metal atoms. • The g-C6N6 nanoribbons adsorb transition metal atoms become indirect narrow band gap semiconductor. [ABSTRACT FROM AUTHOR]

• We performed a computational and theoretical study of FeCrTiAl. • Our calculations indicate that this material undergoes several band structure transitions. • Another interesting feature of FeCrTiAl is that its spin polarization changes sign from negative to positive under pressure. • At the largest considered lattice parameters, this compound exhibits nearly 100% spin polarization. Spin-gapless semiconductors (SGS) represent a new type of compounds with potential applications in novel spintronic devices. Here, we performed a comprehensive computational and theoretical study of FeCrTiAl, a quaternary Heusler compound that was recently predicted to exhibit nearly SGS properties. Our calculations indicate that this material undergoes several band structure transitions from essentially semimetallic phase at smaller lattice constants to nearly type-II SGS at the ground state, then to nearly type-III SGS and further to nearly type-I SGS, as the lattice parameter is increased. Another interesting feature of FeCrTiAl is that its spin polarization changes sign from negative to positive as the volume of the cell increases. At the largest considered lattice parameters, this compound exhibits nearly 100% spin polarization. The mechanical expansion discussed in this text may be achieved, in principle, either by applying an epitaxial strain in thin-film geometry, or by chemical substitution, for example with non-magnetic element of larger atomic radius. We hope that the presented results may provide guidance for further research on mechanical strain induced manipulation of electronic and magnetic properties of spin-gapless semiconductors. [ABSTRACT FROM AUTHOR]

We theoretically investigate the effect of the Rashba interaction on the conductance as well as the valley and spin polarization in an 8- Pmmn borophene superlattice by solving the Dirac–like equation and using the transfer matrix approach. The valley and spin-dependent conductance and spin polarization are effectively controlled by changing the direction of superlattice. The number of the quantum electrostatic potential plays an essential role in quantum transmission properties. Furthermore, in such a superlattice, the conductance of the electrons with spin rotation can be easily adjusted by the Rashba strength, direction of superlattice and electrostatic potential. Thus, borophene superlattice with Rashba interaction can act as a spin and valley splitter. Our work provides a new structure for spin-flip and can be useful for future spintronics and valleytronics applications. • We study the spin-dependent transport properties in an 8- Pmmn borophene superlattice. • Spin rotation can be easily adjusted by Rashba strength and electrostatic potential. • The borophene superlattice under RSOI can use as a spin-converter. • The valley polarization depends sensitively on the number of the barriers. • Magnitude and sign of spin polarization can be adjusted by direction of superlattice. [ABSTRACT FROM AUTHOR]

In this paper, a transition of magnetoresistance (MR) from positive to negative was obtained at room temperature by vacuum annealing of Fe 3 O 4 (128 nm) / Si (with natural SiO 2) heterostructures at 780 °C. Considering the wire-like nanograins with varying length and the effect of interface, the sign of MR is decided by the contribution of two Fe 3 O 4 layers. One is the layer at the Fe 3 O 4 /SiO 2 interface where the scattering of conducting electrons in the natural SiO 2 layer on the top of Si can lead to spin polarization reversal of Fe 3 O 4 and the other is the Fe 3 O 4 far away from the absorbing interface. The reversal sign of MR indicates the dominant contrition of Fe 3 O 4 far away from the absorbing interface as the stabilized SiO 2 phase on top of the Si substrate with fewer ion defects by annealing the Fe 3 O 4 film on natural Si at 780 °C. For the Fe 3 O 4 film prepared on the substrate of corroded Si (chemically etching the natural SiO 2 layer), positive MR is maintained even vacuum annealed at 780 °C, while for the Fe 3 O 4 film on SiO 2 , an additional α-Fe 2 O 3 phase is obtained even negative MR for films both as deposited and annealed at 780 °C. It can be concluded that the SiO 2 layer on top of the substrate plays an important role in the interface and then the magnetotransport properties of the Fe 3 O 4 heterostructures. Well property and negative spin polarization of Fe 3 O 4 film can be obtained by vacuum annealing the Fe 3 O 4 film on Si substrate with a proper thickness of natural SiO 2 layer at 780 °C. • Reversal of positive to negative MR at RT achieved by annealing Fe 3 O 4 /natural Si. • Stable SiO 2 layer prevent the reversal of spin polarization of Fe 3 O 4 to positive. • Comparing with Fe 3 O 4 on SiO 2 and Si with natural SiO 2 corroded respectively. • Preparing thick (128 nm) polycrystalline Fe 3 O 4 films on Si with desired properties. [ABSTRACT FROM AUTHOR]

In this paper, we study the structural, electronic, magnetic, mechanical and thermal properties of Half-Heusler CoMnTe, using the Density Functional Theory (DFT) with the generalized gradient approximation (GGA) and GGA plus the Hubbard correction (GGA+U). The obtained results show that the compound is more stable in γ -phase with the ferromagnetic (FM) configuration than the nonmagnetic (NM) among the three considered structural phases (α , β , γ) and there is no possibility of martensitic transformation under the tetragonal distortion effect. The computed total magnetic moments of CoMnTe by GGA and GGA+U are 4 μ B and 4.13 μ B , respectively, arising mainly from the Mn atom. The obtained density of states and band structures using GGA approach show that the compound exhibits half-metallic behavior with 100% spin polarization. As the Hubbard is added, the electronic properties show an electronic phase transition from half-metallic to metallic behavior with 68% spin polarization. While the thermal and mechanical properties show very small changes, confirming that the studied compound is mechanically and dynamically stable. • CoMnTe compound is more stable in γ -phase with the ferromagnetic configuration. • CoMnTe compound is mechanically and thermodynamically stable. • CoMnTe compound is promising for spintronic applications. [ABSTRACT FROM AUTHOR]

The electronic and transport properties of a series of covalently functionalized graphene sheets m (FeBz) n -G (m , n = 1, 2) are calculated by density functional theory (DFT) and the nonequilibrium Green's function (NEGF) methods. All the studied systems are chemically stable due to the d – π interaction between Fe and graphene. Addition of (FeBz) n (n = 1, 2) introduces a half-metallic behavior: the up-spin state degradates into a semiconductor channel while the down-spin state behaves as a metallic channel. Particularly, two-fold anisotropy magnetism could be obtained, with the ferromagnetic ordering extending either parallel to the graphene plane originated from the Fe- d up-spin state or perpendicular due to the d -electron coupling along the Fe-Bz-Fe-Bz chain in the down-spin state. Because of the trapping effect, attaching (FeBz) n decreases the conductivity. Anisotropy inherited from graphene after functionalized with (FeBz) n (n = 1, 2): zigzag direction has higher conductivity than armchair direction. The number and alignment style of (FeBz) n (n = 1, 2), and the spin-polarized character, all have impacts on the transport property. Our findings provide useful guidelines for achieving graphene-based electronic and spintronic nanodevices by attaching other similar long multi-decker metal-arene systems. [Display omitted] • Electronic and transport properties of functionalized graphene m (FeBz) n -G (m , n = 1, 2) are calculated theoretically. • Addition of (FeBz) n (n = 1, 2) introduces half-metallic behavior. • Ferromagnetic ordering extends not only parallel to the graphene plane but perpendicular to it. • Conductivity is determined by anisotropy inherited from graphene, number and alignment of (FeBz) n , and spin polarization. [ABSTRACT FROM AUTHOR]

In this paper, we study the spin polarization of stationary and moving bright solitons in spin orbit coupled Bose Einstein condensate trapped by a variable shape optical lattice. We particularly investigate the effects of optical lattice parameters, detuning parameter and spin orbit coupling strength on spin polarization. We find that the spin polarization may show different characteristics in different regions of the potential. We also study the dynamical properties of moving bright solitons which change significantly with the optical lattice parameters. The study is performed by using the variational and numerical methods. • Solitons in a variable shape optical lattice potential are investigated. • The parameters effecting the spin polarization are reported. • The dynamical properties of solitons change with the optical lattice parameters. [ABSTRACT FROM AUTHOR]

We use the technique of time-resolved Kerr rotation (TRKR) to measure the electron spin polarization generated by optical spin pumping in an n-type gallium arsenide (GaAs) epilayer when an external electric field is simultaneously applied on the sample. The drift of the electron spins under the influence of the external electric field is captured with spatial scans of the pump–probe separation. A significant decay in the magnitude of electron spin polarization with electric field is observed and is attributed to the increased inhomogeneous broadening caused by the field-induced drift and the hot electron effects. We extend the electric field range to as high as the Gunn threshold field in the measurement and we do not observe a spin amplification effect due to the spin Gunn effect under our experimental scheme. • Optical pump–probe technique is used to study electron spin polarization in n-GaAs. • E-field dependent spin drift and spin decay are measured in spin drag experiments. • Spin decay and amplification effects at E-fields at Gunn threshold regime are probed. [ABSTRACT FROM AUTHOR]

Featured with the large Rashba constant (α R ∼ 4.2 eVÅ) coupled with the ferroelectricity, GeTe has attracted much interest, proposing novel energy-efficient spintronic devices. However, those approaches are hampered by the high hole density of GeTe around 1020-1021 cm−3, which deteriorates both the ferroelectricity and the bulk Rashba effect of GeTe. To solve this problem, we have investigated the superlattices composed of Bi 2 Te 3 and GeTe ([BT|GT] SL), the former of which is known as a topological insulator (TI) with typically n -type conduction and strong spin-orbit coupling. We have investigated the magnetotransport properties of 25 [BT x |GT y ] z SLs with varying thicknesses (x , y : the thickness in the multiples of the unit cell of the respective layer) of each layer and the repetition number (z) systematically. We have observed a minimum carrier density of 5.7 × 1019 cm−3 in [BT 6 |GeTe 6 ] 6 superlattice sample smaller than that (∼4.4 ×1020 cm−3) of GeTe single film by an order. In addition, we have found that some [BT|GT] SLs with reduced carrier density have a larger Rashba constant compared to that of a single GeTe film. This is explained by the change of the spin polarization which can be modulated by the Fermi level in the Rashba band. These results provide a viable way to realize robust ferroelectricity and strong SOC in GeTe-related material systems simultaneously. • A method to modulate the carrier density in GeTe is proposed, enabling the application of FeRSC to spintronic devices. • The Rashba constant is observed to increase as the carrier density decreases in GeTe/Bi 2 Te 3 superlattice systems. • The reduction of the carrier density in GeTe/Bi 2 Te 3 superlattice systems can be explained in terms of the charge transfer. • Growth techniques of high-quality GeTe/Bi 2 Te 3 superlattices are presented. [ABSTRACT FROM AUTHOR]

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

We derive the generalized chiral kinetic equations which are applicable to the fermions with arbitrary mass. We show how the dynamical magnetic-moment distribution function could lead to spin polarization and electric charge separation. We also show how the electric/magnetic moment distribution and pseudoscalar distribution could be induced by vorticity and electromagnetic field in global equilibrium. [ABSTRACT FROM AUTHOR]

Spin-exchange free-relaxation (SERF) co-magnetometer has promising applications in the field of inertial navigation and fundamental physics experiments since its coupled spin ensemble is capable of measuring rotation with ultra-high sensitivity. Electron spin polarization determines the performance of the SERF co-magnetometer directly. In this paper, it is found that there is a non-negligible coupling between the probe light frequency and electron spin polarization. A model of the polarization in relation to the probe light frequency for a hybrid pumping cell is established. This paper discovers the existence of a theoretical optimum frequency that enables a more stable polarization in the model, and an experimental verification is carried out. Experiments results show that when the SERF co-magnetometer operates at this optimization frequency, its short- and long-term stability is significantly enhanced. Further, based on this model, the detuned frequency stabilization technique is proposed. The long-term stability of the probe light frequency is also improved by 43.85% after closing the loop. [Display omitted] • In this paper, it is found that there is a non-negligible coupling between the probe light frequency and electron spin polarization. A model of the relationship between them is established. • It is finds that there is an optimal frequency which can significantly reduce the disturbance of probe system to the SERF co-magnetometer in the response model. • The detuned frequency stabilization technique is proposed based on the model and the long-term stability of frequency is improved by 43.85% after stabilization. [ABSTRACT FROM AUTHOR]

• The external magnetic field dramatically improved the analysis sensitivity of paper-based PEC biochip. • Electron spin polarization boosted photoinduced charge separation in sulfur-defected CdIn 2 S 4 /FeOOH and ferromagnetic ZnFe 2 O 4. • The ferromagnetic ZnFe 2 O 4 nanosphere was utilized as a multiple signal amplifier with strong quenching effects. • Enzymatic catalytic precipitation reaction was introduced for ultrasensitive detection of chlorpyrifos in real samples. Efficient carrier separation plays an utterly pivotal role in enhancing the sensitivity of photoelectrochemical (PEC) analysis. Here we report a concise yet powerful strategy of electron spin polarization induced by magnetic stimulation, to effectively modulate the efficiency of charge separation in a paper-based PEC (μ-PEC) sensing system. The electronic configuration of the sulfur-defected CdIn 2 S 4 /FeOOH photoactive matrix and ferromagnetic ZnFe 2 O 4 signal label were regulated via the electron parallel alignment along with spin state flip and reconstruction at particular active sites under external magnetic field, significantly facilitating the separation of photoinduced carriers. As a proof-of-concept application, the magnetic-triggerable spin-state reconfiguration coupled with enzymatic catalytic precipitation reaction was developed for detection of chlorpyrifos with a wide linear range of 10-2.5-106 ng mL−1 and low detection limit of 0.67 pg mL−1. This work provides the basis for understanding the role of magnetic stimulus in tailoring charge separation and constructing a universal strategy for high performance μ-PEC bioanalysis. [ABSTRACT FROM AUTHOR]

The spin resolved electronic transport behavior of ZnO nanowires (ZnONWs) linked to electrodes is investigated using first principles calculations within Density Functional Theory incorporating the Hubbard (U) term. A defect (resulting from Zn vacancy) in ZnO, as well as the use of Ni electrodes, have a significant influence on the electronic structure properties. They improve the magnetic moment of the system and generate a spin-asymmetric spectra. The ZnONWs linked to the Ni electrodes are probed for spin resolved differential conductance and current. Although the spin down differential conductance curves have a similar trend, the variations in spin up conductance are dissimilar. ZnONW-based devices appear promising for prospective spintronic applications due to their nearly half-metallic behavior around the Fermi energy and acceptable spin polarization in current. • ZnO nanowires are promising for spintronic applications. • The magnetism in ZnO nanowire-based devices can be enhanced using a vacancy and/or Ni electrodes. • Spin polarization in current and DOS is appreciable. [ABSTRACT FROM AUTHOR]

The dwell time is calculated for electron in a novel magnetic nanostructure with zero average magnetic fields, which is realized experimentally by constructing three nanosized ferromagnetic stripes on top and bottom of the InAs/Al x In 1-x As heterostructure. Although structural magnetic fields are averagely equal to naught, the dwell time is still dependent on electron spins owing to the spin-field interaction. Due to the dependence of effective potential experienced by electron on structural parameters (such as magnetic strength and device width), spin-polarized dwell time can be conveniently modulated by reasonably fabricating ferromagnetic stripes. As a result, this novel magnetic microstructure can act as a temporal electron-spin splitter for spintronic device applications. • Dwell time is calculated for electron in a novel SMQM. • Dwell time still depends on electron spins in spite of zero average magnetic field. • Spin-dependent dwell time is manipulated by incident angle, magnetic strength and structural width. • A temporal spin splitter is achieved for spintronics device applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multifunctional Co atoms are doped on the twin Mn 0.3 Cd 0.7 S homojunction surface. • Co atoms regulate S electron property and build a fast H-migration channel at S sites. • H migration endows sufficient H to sustain HER and reduces the H 2 evolution barrier. • Co atoms on the cubic phase act as OER active sites to enhance oxidation activity. • The Z-scheme interfacial charge-transfer mechanism is achieved. Low kinetics of water dissociation, unfavorable hydrogen adsorption, and high water-oxidation barriers restrict the photocatalytic overall water splitting (OWS) efficiency over sulfides. Herein, multifunctional Co atoms are doped on the twin Mn 0.3 Cd 0.7 S homojunction surface for efficient photocatalytic hydrogen (H 2) and oxygen (O 2) evolution. An ultrafast hydrogen atom (H*) migration channel bridging the water dissociation/H 2 evolution step is established between cubic-S and hexagonal-S sites by introducing Co atoms, facilitating the HER kinetics. Specifically, Co atoms regulate the electron properties of neighboring S atoms and weaken their charge accumulation, which promotes cubic-S sites to capture sufficient H* from the water dissociation zone and accelerates hexagonal-S sites to release H 2 through the H* migration channel. Meanwhile, unsaturated Co atoms on the cubic phase as oxygen evolution reaction (OER) sites promote water deprotonation and optimize the kinetics of the rate-determining step to form OOH* intermediate, enhancing water oxidation activity. Co atoms strengthen the internal electric field of the homojunction and local polarized electric field by increasing the work function difference between the two phases and introducing the high spin polarization, inhibiting the bulk and surface recombination of photogenerated carriers. The Co 0.01 Mn 0.29 Cd 0.7 S exhibits visible-light-driven H 2 and O 2 evolution rates of 443.12 and 219.67 μmol g−1 h−1, about 50 times that of the Mn 0.3 Cd 0.7 S. This work provides some guidance for the design of homojunction photocatalysts with efficient OWS performance. [ABSTRACT FROM AUTHOR]

• Superconducting NbN has low spin–orbit coupling and makes a good candidate to perform meservey-tedrow measurements. • Using the robust surface oxide, tunnel junctions on NbN can be fabricated using a facile process without lithography. • Due to the high t c of NbN (∼16.5 K), one can perform the spin polarization measurement of ferromagnets at temperatures at high as 1.57 K. We report a two-step process for the fabrication of superconductor-insulator-normal metal tunnel junctions using NbN as the superconducting electrode and its surface oxide as the insulating tunnel barrier, and investigate its efficacy in measuring spin-polarisation of ferromagnets using the Meservey-Tedrow technique. We observe that for NbN film thickness below 10 nm, under the application of parallel magnetic field, the superconducting density of states show clear "Zeeman" splitting into spin-up and spin-down sub-bands. Tunnelling measurements on devices where ferromagnetic Co is used as the normal electrode shows that these devices can be used to measure spin polarisation of a ferromagnet at temperatures up to 1.6 K. The simplicity of our fabrication process makes NbN a very attractive candidate for spin polarisation measurements. Some limitations of this process are also discussed. [ABSTRACT FROM AUTHOR]

Within the nuclear DFT approach, we determined the magnetic dipole and electric quadrupole moments for paired nuclear states corresponding to the proton (neutron) quasiparticles blocked in the π 11 / 2 − (ν 13 / 2 +) intruder configurations. We performed calculations for all deformed open-shell odd nuclei with 63 ≤ Z ≤ 82 and 82 ≤ N ≤ 126. Time-reversal symmetry was broken in the intrinsic reference frame and self-consistent shape and spin core polarizations were established. We determined spectroscopic moments of angular-momentum-projected wave functions and compared them with available experimental data. We obtained good agreement with data without using effective g -factors or effective charges in the dipole or quadrupole operators, respectively. We also showed that the intrinsic magnetic dipole moments, or those obtained for conserved intrinsic time-reversal symmetry, do not represent viable approximations of the spectroscopic ones. [ABSTRACT FROM AUTHOR]

First, I study the analogy between the magnetization of a material and the spin polarization of particles in a fluid. Using the relativistic version of the Barnett effect, i.e. the magnetization of a material induced by mechanical rotation, the spin polarization induced by thermal vorticity is obtained within a purely classical model, where spin is treated as an intrinsic magnetic moment and rotation is included as a non-inertial effect. I argue that since spin polarization induced by thermal vorticity can be obtained in a classical theory, it can not be dominated by quantum anomalies. Second, the spin polarization induced by magnetic field is obtained for a fluid at local thermal equilibrium using statistical quantum field theory. The obtained formula is valid beyond the weak field approximation and when contributions from the non-homogeneity of the magnetic field are small. The exact form of spin polarization is studied for a free Dirac field at global equilibrium, and, like magnetic susceptibility, it oscillates according to the de Haas - van Alphen effect. Finally, I briefly review how magnetic field contributes to the difference between the spin polarization of Λ and Λ ¯ observed in heavy-ion collisions. [ABSTRACT FROM AUTHOR]

The investigation of magnetic domain wall resistance (DWR) in epitaxial Co 2 MnAl (CMA) thin films, a Heusler alloy, has revealed a remarkable phenomenon of sign change. This intriguing behavior is attributed to the half-metallic band structure with high spin polarization, as verified by negative anisotropic magnetoresistance in the two-current model. In this way, the scattering relaxation time for the majority and minority electrons, which is primarily determined by the density of states of majority and minority electrons, undergoes a dramatic change in the vicinity of the half-metallic band gap. This results in an unusual upturned relaxation time ratio, leading to the sign change of intrinsic DWR. These findings deepen our understanding of the intricate dynamics of spin-dependent phenomena in half metals and shed light on the entangled magnetoresistance in Heusler alloy with high spin polarization. • Successful demonstration of sign change in magnetic domain wall resistance (DWR) in Co 2 MnAl (CMA) thin films. • Negative anisotropic magnetoresistance proves the high spin-polarization of CMA in the two-current model. • Unique half-metallic band structure and high spin polarization of CMA attributed to sign change in DWR. • Dramatic change in relaxation time ratio near half-metallic band gap leads to intrinsic DWR sign change. [ABSTRACT FROM AUTHOR]

In the spin-exchange relaxation-free (SERF) comagnetometer, the transverse nuclear spin relaxation associated with the electron spin polarization gradient restricts the low-frequency magnetic-field suppression ability and self-compensation performance. A three-dimensional model and a measurement method of polarization gradient relaxation rate (PGRR) in the SERF comagnetometer are proposed in this paper. A plateau of PGRR is discovered and well explained by the model. The proposed measurement method confirms that the PGRR accounts for 90 % ∼ 98 % of the transverse nuclear spin relaxation in the SERF comagnetometer. In addition, the model guides the selection of system parameters to manipulate the polarization distribution, thereby the PGRR is reduced by 14.88 times from 0.02166 1/s to 0.00145 1/s. This research supports improving the long-term stability of the SERF comagnetometer, and the proposed model and method can be extended to other atomic sensors, such as the SERF magnetometer and nuclear magnetic resonance gyroscope. • A three-dimensional polarization gradient relaxation rate (PGRR) model is proposed. • A plateau of PGRR is discovered and well explained by the three-dimensional model. • The PGRR accounts for 90% ∼ 98% of the nuclear spin transverse relaxation. • The PGRR is innovatively separated and quantized in the atomic comagnetometer. • The model guides system parameters selection, reducing the PGRR by 14.88 times. [ABSTRACT FROM AUTHOR]

For the development of low-power spin-multifunctional devices, we have explored the spin-dependent transport properties of nanodevices based on zigzag graphene nanoribbons bridged respectively by oblique, horizontal, and vertical connecting biphenyl molecules. Utilizing the first-principles calculations associated with the non-equilibrium Green's function methods, we found the superb transport results demonstrate that almost 100% spin polarization exists for the obliquely connected and horizontally connected biphenyl molecules devices in the parallel state (P). All of the designed devices exhibit excellent dual spin filtering efficiency and rectification effect in the antiparallel state (AP) with the rectification ratios up to 103, 104, and 105 for obliquely, horizontally, and vertically connected model devices, respectively. Simultaneously, a pronounced negative differential resistance effect can be observed in these devices independent of the spin state. Moreover, the thermal spin transport properties of the obliquely connected model device reveal an apparent Seebeck effect. Then, the length effect on the spin-resolved transport properties for the obliquely connected device have been conducted. Results reveal that the current values are highly tunable by changing the length of obliquely connected biphenyl molecules in the P state. Meanwhile, the doual spin filtering effect still remains, but its rectification effect gradually disappears with the increasing length of center scattering region in AP state. This study provides new insights into the design of multifunctional spin carbon-based and low power consumption devices. • Almost 100% spin polarization and negative differential resistance effect in the parallel configuration are obtained in the all devices. • Each of the designed devices exhibits excellent dual spin filter efficiency and rectification effect in the antiparallel configuration. • A distinct spin Seebeck effect was revealed in antiparallel configuration for the obliquely connected device. • It is found that the spin filtering property of the obliquely connected device independ on the length, while the rectification effect exhibits a length-dependent character. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novel types of vertical hybrid Janus heterostructures of triclinic and monoclinic symmetries based on doped twisted bilayer graphenes with large rotational angles were proposed and studied using PW PBC DFT electronic structure calculations. • Regularly opposed superperiodic sublattices of fluorine and aluminum adatoms were used to induce structural charge polarization, and uncompensated spin moments up to 1.05 µ B per unit cell, caused by local intense transverse electric fields generated by ferromagnetically aligned spin polarization of entire lattices. • TBG twisting angles can determine the spin states in strongly polarized TBG-based Janus heterostructures, where spin polarization of the heterostructures is mostly determined by partial carbon and fluorine electronic states localized in the vicinity of the Fermi level, whereas Al adatoms mostly determine the rate of charge polarization and symmetry and intensity of the internal transverse electric field. • The strong dependence of the spin states of TBG-based Janus heterostructures upon twisting angle combined with superlubricant properties of twisted graphenes makes them promising materials for different spin-related applications like spin photovoltaics and magnetostrictive sensors. The atomic and electronic structure of superperiodic vertical hybrid Janus heterostructures based on doped twisted bilayer graphenes were theoretically developed and studied using electronic structure calculations. Regularly opposed superperiodic sublattices of fluorine and aluminum adatoms were used to induce structural charge polarization, and uncompensated spin moments up to 1.05 µ B per unit cell, caused by local intense transverse electric fields generated by ferromagnetically aligned spin polarization of entire lattices. It was shown that spin polarization of the heterostructures is mostly determined by partial carbon and fluorine electronic states localized in the vicinity of the Fermi level, whereas superlattices of Al adatoms mostly determine the rate of charge polarization, the symmetry, and intensity of the internal transverse electric field up to −0.018 e 2 / Å. It was shown that proposed heterostructures may display advanced electronic spin, entanglement and magnetostriction properties perspective for various spin- and quantum-related applications. [ABSTRACT FROM AUTHOR]

• Effect of a δ-potential on temporal spin splitter based on magnetic microstructure is explored theoretically. • Spin-polarized dwell time still exists in the device with a δ-potential. • Spin polarization ratio can be controlled by changing weight or position of δ-potential. • Acontrollable temporal spin splitter can be achieved for spintronics device applications. We theoretically investigate the effect of a δ-potential to a temporal spin splitter for electron in a semiconductor magnetic quantum microstructure (SMQM), which is realized by patterning a perpendicularly-magnetized ferromagnetic stripe on top of InAs/Al x In 1-x As. The dwell time for electron in the δ-doped SMQM is still spin polarized, because electron spin interacts with structural magnetic field. The spin-dependent dwell time is modulated by switching the δ-potential owing to the dependence of effective potential felt by electron on the δ-doping. These significant findings demonstrate that such a δ-doped SMQM acts as a manipulable temporal electron-spin splitter, which may be helpful for design of spintronic devices. [ABSTRACT FROM AUTHOR]

Structural, electronic and magnetic properties of the chromium (Cr) nanostructure formation on GaAs(1 1 1)–(2 × 2) surfaces are investigated. Studies are performed by first principles total energy calculations within the periodic spin polarized density functional theory plus Hubbard correction (GGA + U) with 1 < U < 5 eV, as developed in the PWscf code of the quantum ESPRESSO package. The chromium adsorption and incorporation into the GaAs(1 1 1)-(2 × 2) atomic structure are investigated on both gallium and arsenic terminated surfaces. Different coverage of Cr is considered from ¼ monolayer (ML) up to a full ML to determine the relaxed configurations and the most favorable structure. High symmetry sites are considered to explore the Cr adsorption and incorporation into the GaAs structure, these are: H3, T4, Top and Bridge. Surface atomic structures contain different number of atoms therefore to determine the most stable atomic geometry the surface formation energies are constructed. On the As terminated surface, under As rich conditions the CrAs bilayer formation is the most favorable structure. On the Ga terminated surface, under Ga rich conditions the Cr trimer formation is the most favorable configuration. Electronic properties of the most stable structures are investigated by calculating the total density of states (DOS) and projected DOS. Results indicate that the most favorable nanostructures exhibit metallic behavior with antiferromagnetic characteristics. [ABSTRACT FROM AUTHOR]

The magnetic properties of nonmetal (NM) doped (H, B, C, Si, N, P, As, O, S, Te, F, Cl, Br or I) monolayer MoSe 2 were investigated by first principle calculations. We have found that NM dopants with odd number of valence electrons can induce magnetism; on the contrary, NM dopants with even number of valence electrons cannot induce magnetism. More importantly, half metallic property has been found for H-, B-, F-, Cl-, Br- and I-doped MoSe 2 , characterized with 100% spin-polarization around the Fermi level. This work has important guidance for the realization of spin devices on monolayer MoSe 2 . [ABSTRACT FROM AUTHOR]

We have studied the partially spin polarized fractional quantum Hall states using Chern Simon's theory and plasma picture proposed by Halperin. Using these theoretical techniques we have tried to find the stable polarized states of different filling fractions observed in experiments. We have calculated the ground state energies of those states and also pair correlation function. We have described the nature of the states by the behaviour of this quantity. In our study, we have seen that the partially polarized states, which do not fit with Jain's composite fermion description are basically the mixed state of up-spin liquid phase and down-spin solid phase. [ABSTRACT FROM AUTHOR]

Spin transport properties in a non-uniform quantum wire (QW) in the presence of both the Rashba and Dresselhaus spin–orbit couplings (SOCs) is investigated by using the non-equilibrium Green's function (NEGF) method combined with the Landauer Büttiker formalism. It is found that such a non-uniform quantum wire exhibits considerable spin polarization in its conductance in the influence of both the Rashba and Dresselhaus SOCs, and that the two SOCs' strengths strongly affect both the magnitude and sign of the electron spin polarization. Interestingly, the Rashba and Dresselhaus SOCs play the same modulating role in the electron spin polarization. The proposed nanostructure can potentially be utilized to devise an all-electrical spintronic device. [ABSTRACT FROM AUTHOR]

Spin-polarized, first-principles total energy calculations have been performed to investigate the structural, electronic and magnetic properties of the chromium nitride (0 0 1) surface. Different approximations were used to treat the non-classical exchange correlation energy: LDA, GGA, LDA + U (3 eV ≤ U ≤ 5 eV) and GGA + U (1 eV ≤ U ≤ 4 eV). It was found that LDA + U with U = 4 eV describes correctly the structural, electronic and magnetic properties of bulk CrN. The CrN (0 0 1) surface has been investigated, employing the surface formation energy (SFE) formalism. For the surface in the cubic phase, three different structures were found to be stable: an ideally terminated surface, one with no nitrogen atoms in the second layer, and one with half of the nitrogen atoms missing in the second layer. In the case of the orthorhombic surface, only the ideal surface is stable in all the range of the chemical potential. Density of States (DOS) calculations show a metallic behavior for all the stable surface structures, with the main contribution around the Fermi level coming from Cr-d orbitals. The effect of nitrogen vacancies is clearly observed with an increase in the metallic behavior in the structures having less nitrogen atoms. [ABSTRACT FROM AUTHOR]

Spin-polarized density functional theory is used to investigate the formation energetics and magnetic properties of Ca/transition metal TM (TM = Sc, Ti, V, Cr, Mn, Fe, Co, Ni, and Cu) doped CaZrO 3 systems. A strong interdependence of formation energy and TM dopant size (ionic radii) is evident, which increases solely with the increase of dopant atomic number. Our results elucidate that Co@Zr, Cr@Zr, Fe@Zr, and V@Zr doped systems show half-metallic nature due to partial filling of d -orbitals with a reasonable charge carrier density of ∼10 21  cm −3 , while Ca@Zr and Cu@Zr doped systems exhibit p -type ferromagnetism because of deficiency of electrons. In contrast, Sc-dopant reveals as p -type non-magnetic due to strong hybridization. Furthermore, Ti@Zr, Mn@Zr, and Ni@Zr doped CaZrO 3 systems, depict non-magnetic behavior. Interestingly, Mn@Zr doped system contains high magnetic moment of 3 μ B and show insulating nature. The findings of present calculations yield a wide avenue for practical applications of these doped systems in spintronics. [ABSTRACT FROM AUTHOR]

Non-spin-polarized electronic structures and Fermi surface properties of RX 2 Al 20 ( R  =  La, Ce, Yb, Th, U; X  = Ti, V, Cr, Mn) intermetallic compounds were calculated using the full potential all-electron local orbital (FPLO) approach in the framework of the local density approximation (LDA). Trends of the magnetism are discussed in terms of the characteristics of X - 3 d bands with a quantitative analysis of the relationship between band electron filling and crystal electric field splitting. Since coordination icosahedra of X -atoms have small trigonal distortion, crystal electric field splits the fivefold degenerate X -3 d state into low-energy singlet a 1 g and two higher-energy doublets e g . In R Ti 2 Al 20 and R V 2 Al 20 the population of the related 3 d sub-band is not sufficient to cause energetically favorable spin polarization, whereas magnetic instabilities develop in the R Cr 2 Al 20 series. Finally, a manifestation of strong repulsive interactions between itinerant Mn- d electrons become most pronounced in ferromagnetic UMn 2 Al 20 . The influence of non-magnetic R - f states on magnetic and thermodynamic properties is discussed with special emphasis on the role of the f – p and f – d hybridization. For LaTi 2 Al 20 and LaV 2 Al 20 the calculated quantum oscillation frequencies are in accord with experimental reports. [ABSTRACT FROM AUTHOR]

Abstract Spin-polarization can be essential in many cases of vital importance to the procedures of chemical and biological function. Its realization and utilization have been drawing intensively growing attention for over half a century, whereby numerous strategies get developed with related mechanisms proposed. Furthermore, spintronics has evolved as a scientific domain in which efforts are made to better understand the electron's intrinsic quantum properties based on its angular momentum. To date, an effective approach for aligning the electrons’ spin usually employs an external magnetic field, which may not be viable or efficient in all applications. This review emphasizes on the advances of spintronics where the polarization of spin is able to be implemented by other means than an external magnetic field. The key role of chiral structures for filtering the electrons on spin along with the approaches applied to monitor the polarization of spin will get introduced. Moreover, theoretical frameworks rationalizing the experimental results obtained are also presented herein. The thread running through all of these will be the proposal and evolution of Chiral-Induced Spin Selectivity (CISS) effect. Graphical abstract fx1 Highlights • Chiral structure is spin-selective when being applied as a pathway for electron transfer. • CISS (Chiral-Induced Spin Selectivity) effect can be utilized to manufacture high-efficiency microelectronic devices. • CISS effect provides sound explanations for some chemical and biological procedures such as precise bio-recognition. [ABSTRACT FROM AUTHOR]

Dark matter, one of the important portion of the universe, could affect the visible matter in neutron stars. An important physical feature of dark matter is due to the spin of dark matter particles. Here, applying the piecewise polytropic equation of state for the neutron star matter and the equation of state of spin polarized self-interacting dark matter, we investigate the structure of neutron stars which are influenced by the spin polarized self-interacting dark matter. The behavior of the neutron star matter and dark matter portions for the stars with different values of the interaction between dark matter particles and spin polarization of dark matter is considered. In addition, we present the value of the gravitational redshift of these stars in different cases of spin polarized and self-interacting dark matter. [ABSTRACT FROM AUTHOR]

We investigate gap solitons in spin–orbit-coupled Bose–Einstein condensates in bichromatic optical lattices and mainly focus the effect of the secondary periodic potential trap on the gap solitons. The gap solitons and linear Bloch waves are obtained by solving coupled Gross–Pitaevskii equations in bichromatic optical lattice. The results show that parity symmetry plays an important role when the detuning between the Raman beam and energy levels of the atoms is zero. It is shown that the soliton amplitude increases with the increasing secondary periodic potential well depth. The gap solitons become spin polarization for the case of nonzero detuning. Linear stability analysis method has been employed to investigate the stability of gap solitons located in the first and second band gaps. The results prove that the periodic secondary potential trap depths have important effects on the stability of gap solitons. [ABSTRACT FROM AUTHOR]

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

Facing physical limits to further development, modern electronics explores alternative approaches. One of the most promising routes is offered by spintronics employing spin degree of freedom. Silicon spintronics is especially important due to the central technological role of Si. This technology requires non-equilibrium spin polarization in non-magnetic Si. The ferromagnetic semiconductor EuO has been justified as a promising candidate for electrical spin injection into Si. Here, we report the first fabrication of the EuO(1 1 1)/Si(1 1 1) structure – a magnetic material with a polar heterointerface – employing a special synthetic procedure. Structural characterization proves an atomically sharp interface and monocrystalline quality of the films while magnetic measurements match the bulk properties of EuO. [ABSTRACT FROM AUTHOR]

Using the tight-binding formalism, we explore the effect of weak disorder upon the conductance of zigzag edge silicene nanoribbons (SiNRs), in the limit of phase-coherent transport. We find that the fashion of the conductance varies with disorder, and depends strongly on the type of disorder. Conductance dips are observed at the Van Hove singularities, owing to quasilocalized states existing in surface disordered SiNRs. A conductance gap is observed around the Fermi energy for both edge and surface disordered SiNRs, because edge states are localized. The average conductance of the disordered SiNRs decreases exponentially with the increase of disorder, and finally tends to disappear. The near-perfect spin polarization can be realized in SiNRs with a weak edge or surface disorder, and also can be attained by both the local electric field and the exchange field. [ABSTRACT FROM AUTHOR]

Differential cross sections and polarization correlations for the scattering of relativistic spin-polarized leptons from unpolarized ground-state sodium nuclei are calculated within the distorted-wave Born approximation (DWBA). Various nuclear ground-state charge distributions are probed. Besides potential scattering, also electric C2 and magnetic M1 and M3 transitions are taken into account. It is shown that even for a light nucleus such as 23 Na there are considerable electron–positron differences at high collision energies and large scattering angles. In particular, the symmetry of the Sherman function with respect to a global sign change, as predicted by the second-order Born approximation when replacing electrons by positrons, is broken whenever the diffraction structures come into play beyond 100 MeV. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) materials comprising of graphene, hexagonal boron nitride (hBN) and transition metal dichalcogenides (TMDs) have revealed fascinating properties in various spintronic architectures. Here, we review spin valve effect in lateral and vertical magnetic junctions incorporating 2D materials as non-magnetic layer between ferromagnetic (FM) electrodes. The magnetic field dependent spin transport properties are studied by measuring non-local resistance (R NL ) and relative magnetoresistance ratio (MR) for lateral and vertical structures, respectively. The review consists of (i) studying spin lifetimes and spin diffusion length thereby exploring the effect of tunneling and transparent contacts in lateral spin valve structures, temperature dependence, gate tunability and contrasting mechanisms of spin relaxation in single layer graphene (SLG) and bilayer graphene (BLG) devices. (ii) Perpendicular spin valve devices are thoroughly investigated thereby studying the role of different 2D materials in vertical spin dynamics. The dependence of spin valve signal on interface quality, temperature and various other parameters is also investigated. Furthermore, the spin reversal in graphene-hBN hybrid system is examined on the basis of Julliere model. [ABSTRACT FROM AUTHOR]

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

In this paper, using first-principles calculations based on density-functional theory, the electronic structures, magnetic properties, and half-metallicity in the bulk and (001) surface of quaternary Heusler alloy CoNbMnSi are studied. For the bulk, the CoNbMnSi compound shows half-metallicity with a band gap of 0.5 eV in the down-spin direction at a equilibrium lattice constant of 5.88 Ǻ. At a similar equilibrium lattice constant, the half-metallicity confirmed in the bulk CoNbMnSi, is ruined at both NbSi- and MnCo-terminated (001) surfaces and subsurfaces. Based on the magnetic property calculations, the magnetic moments of Mn and Nb atoms at the (001) surfaces increase with respect to the corresponding bulk values, while the magnetic moment of Co and Si atoms decreases. The spin-polarization ratio clearly decreases below 75% for (001) surfaces and subsurfaces of the CoNbMnSi alloy. [ABSTRACT FROM AUTHOR]

The present study is conducted to evaluate the spin polarization in two pyrene and Triphenylene graphene nanoflakes. All calculations are performed using non-equilibrium Green's function (NEGF) method. The obtained results show that, graphene has no magnetic property and using Pyrene nanoflake results in a better spin switching at extreme magnetic fields. On the contrary, when applying magnetized electrodes, depending on the direction of magnetization of the two electrodes (either parallel or anti-parallel), different spin polarization diagrams are obtained. In this situation, it is observed that, in the case of electrodes magnetization in Triphenylene nanoflake a better spin switching is reached. [ABSTRACT FROM AUTHOR]

The quantum second virial coefficient B q has been used as a tool to quantify the average magnitude and sign of interactions between T↓ atoms. A negative B q represents an overall attractive interaction. It is found that B q of dilute gas is related to formation of small clusters. A very negative B q indicates that interactions would be expected to be strongly attractive and predicts aggregation atoms to form clusters. It is concluded that B q may be used as a predictor of formation of small spin-polarized tritium (T↓) clusters. [ABSTRACT FROM AUTHOR]

On the basis of first principles calculations, the electronic structures and magnetic properties of quaternary Heusler alloys RbCaNZ (Z = O, S, and Se) were studied. The negative formation energies indicated that all these compounds were thermodynamically stable and thus may be experimentally synthesized at appropriate conditions in the future. The results showed that Y I structure was the most favorable configuration among the three possible structures. All compounds were found to be half-metallic ferromagnets. The characteristic of energy bands and origin of half-metallicity were also verified. The total magnetic moments of RbCaNZ (Z = O, S, and Se) compounds were obtained 2 μ B per formula unit, which were in an agreement with Slater-Pauling rule ( M tot = 12  −  Z tot ). Half-metallicity was preserved at ranges of 5.06–8.36 Å, 5.96–8.81 Å, and 6.13–8.73 Å for RbCaNO, RbCaNS, and RbCaNSe compounds, respectively, which show that these quaternary Heusler compounds may be potential candidates in spintronic applications. [ABSTRACT FROM AUTHOR]