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Research on intragranular acicular ferrite inclusions has demonstrated that high-melting-point oxide MgAl2O4 cores and composite inclusions precipitated by Ti2O3 adhesion can be used as effective nucleation particles in oxide metallurgy. However, the microscopic mechanism underlying this adsorption behavior remains unclear. Hence, in this study, the adsorption and polymerization mechanisms of Ti2O3 on the MgAl2O4(100)Mg- and MgAl2O4(111)O3(Mg)-terminal surfaces in steel were studied using first-principles calculations based on density functional theory. The calculation based on the first principles of DFT and performed by the CASTEP code under plane wave basis set. The exchange correlation energy and correlation effects were described by generalized gradient approximation (GGA) using the Perdew–Burke–Ernzerhof (PBE) function. Spin polarization was considered in all calculation. Ultrasoft pseudopotentials (USPP) was employed to describe the electron-ion interactions. The energy cutoff for the plane wave basis was set at 620 eV in the current work. For the Brillouin zone sampling, we carried out 3 × 3 × 3 k-points mesh for MgAl2O4 bulk using the method of Monkhorst-Pack. A vacuum layer of 20.0 Å is added above the top surface of MgAl2O4 to eliminate the interaction of the normal periodic repetition of the surfaces. In all the surface calculations, the use of symmetry in bulk crystal was failed and k-point grids is set to 3 × 3 × 1. The results of this study revealed that when the most stable adsorption positions of Ti2O3 on the surface of MgAl2O4(100)Mg- and MgAl2O4(111)O3(Mg)-terminal are located at TAl and FMg, the adsorption energy is the highest and the most stable. The most stable adsorption configurations are located on vertical and parallel (P1) surfaces. Through comparative analysis, the best surface for Ti2O3 adsorption was found to be the MgAl2O4(111)O3(Mg)-terminal surface, and the adsorption behavior mainly occurred on the first layer of atoms on the surface. The best adsorption configuration was P1, and the best adsorption mode occurred when Ti2O3 formed three rings connected in pairs with the surface and embedded in the surface of the MgAl2O4(111)O3(Mg)-terminal. This study provides insights into the adsorption polymerization mechanisms of MgAl2O4–Ti2O3 complex inclusions in steel that could facilitate the fabrication of novel low-melting-point oxides and sulfides. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) half-metallic magnets are expected to achieve breakthroughs in the field of spintronics and quantum computation due to their 100% spin polarization and non-dissipative ballistic transport characteristics. However, the current availability of practical applications for these materials is limited. In this paper, a new 2D material NiVS6As2 is predicted based on density functional theory (DFT). It has a ferromagnetic ground state with a high Curie temperature, TC = 150 K and half-semi-metal (HSM) band structure protected by a structural symmetry degeneracy point on the Fermi surface, which can be controlled by an electric field and strain. When an out-of-plane electric field is applied, NiVS6As2 shows a Chern insulator with a quantum anomalous Hall (QAH) effect. These results expand the family of 2D magnetic semimetals, and provide new theoretical inspiration for understanding the protection of degenerate point symmetry. [ABSTRACT FROM AUTHOR]

High-quality antiferromagnetic Mott insulator thin films of LaTiO3 (LTO) were epitaxially grown onto SrTiO3 (STO) (110) substrates using the pulsed laser deposition. The LTO/STO heterostructures are not only highly conducting and ferromagnetic, but also show Kondo effect, Shubnikov-de Haas (SdH) oscillations with a nonzero Berry phase of π, and low-field hysteretic negative magnetoresistance (MR). Angle-dependent SdH oscillations and a calculation of the thickness of the interfacial conducting layer indicate the formation of a 4-nm high mobility two-dimensional electron gas (2DEG) layer at the interface. Moreover, an amazingly large low-field negative MR of ∼61.8% is observed at 1.8 K and 200 Oe, which is approximately one to two orders of magnitude larger than those observed in other spin-polarized 2DEG oxide systems. All these results demonstrate that the 2DEG is spin-polarized and the 4-nm interfacial layer is ferromagnetic, which are attributed to the presence of magnetic Ti3+ ions due to interfacial oxygen vacancies and the diffusion of La3+ ions into the STO substrate. The localized Ti3+ magnetic moments couple to high mobility itinerant electrons under magnetic fields, giving rise to the observed low-field MR. Our work demonstrates the great potential of antiferromagnetic titanate oxide interface for designing spin-polarized 2DEG and spintronic devices. [ABSTRACT FROM AUTHOR]

The experimental efficiency has been a central concern for time-consuming experiments. Spin- and angle-resolved photoemission spectroscopy (spin-resolved ARPES) is renowned for its inefficiency in spin-detection, despite its outstanding capability to directly determine the spin-polarized electronic properties of materials. Here, we investigate the potential enhancement of the efficiency of spin-resolved ARPES experiments through the integration of measurement informatics. We focus on a representative topological insulator Bi 2 Te 3 , which has well-understood spin-polarized electronic states. We employ Gaussian process regression (GPR) to assess the accumulation of spin polarization information using an indicator known as the GPR score. Our analyses based on the GPR model suggest that the GPR score can serve as a stopping criterion for spin-resolved ARPES experiments. This criterion enables us to conduct efficient spin-resolved ARPES experiments, significantly reducing the time costs by 5-10 times, compared to empirical stopping criteria. [ABSTRACT FROM AUTHOR]

Alkaline earth halides garnered interest in spintronics research due to their longer spin relaxation time. Employing first principles calculations, 3d transition metal (TM)-substituted magnesium bromide (MgBr2) monolayers have been reported for the first time for potential spintronics applicability. Among these systems, Cr-, Cu- and Fe-substituted MgBr2 monolayers showed half-metallicity that can be used in ultra-fast spintronics because of high spin polarization. Bipolar magnetic semiconducting (BMS) nature was observed in Mn-substituted monolayer that enables spin control and manipulation by external bias voltage. The formation energy of TM dopants under Br-rich condition showed the feasibility of TM substitution. The half-metallic TM-substituted systems showed a large spin channel gap which inhibits spin leakage. The spin flip gap in BMS monolayer was feasible for practical device operation. Additionally, significant magnetic anisotropy energy per dopant has been observed with a ferromagnetic coupling in Cr-, Cu- and Fe-substituted systems, while antiferromagnetic coupling was shown by Mn- and V-substituted monolayers. Monte Carlo (MC) simulation revealed a near room temperature magnetic phase transition temperature. Robustness of the half-metallicity and BMS spin flip gap was ascertained with strain-mediated density of states which is of importance while fabrication upon a lattice mismatch between substrate. The magnetic transition temperature tuned by applied either compressive or tensile strain is also performed. Hence, electronic and magnetic studies revealed 3d TM element-substituted monolayer MgBr2 to be a potential system in spintronics applications. [ABSTRACT FROM AUTHOR]

Spin textures, i.e., the distribution of spin polarization vectors in reciprocal space, exhibit diverse patterns determined by symmetry constraints, resulting in a variety of spintronic phenomena. Here, we propose a universal theory to comprehensively describe the nature of spin textures by incorporating three symmetry flavors of reciprocal wavevector, atomic orbital, and atomic site. Such an approach enables us to establish a complete classification of spin textures constrained by the little co-group and predict some exotic spin texture types, such as Zeeman-type spin splitting in antiferromagnets and quadratic spin texture. To illustrate the influence of atomic orbitals and sites on spin textures, we predict orbital-dependent spin texture and anisotropic spin-momentum-site locking effects, and corresponding material candidates validated through first-principles calculations. The comprehensive classification and the predicted new spin textures in realistic materials are expected to trigger future spin-based functionalities in electronics. [ABSTRACT FROM AUTHOR]

The effect of external magnetic fields on the behavior of the Zhang-Rice exciton in NiPS3, which captures the physics of spin-orbital entanglement in 2D XY-type antiferromagnets, remains unclear. This study presents systematic study of angle-resolved and polarization-resolved magneto-optical photoluminescence spectra of NiPS3 in the Voigt geometry. We observed highly anisotropic, non-linear Zeeman splitting and polarization rotation of the Zhang-Rice exciton, which depends on the direction and intensity of the magnetic field and can be attributed to the spin-orbital coupling and field-induced spin reorientation. Furthermore, above the critical magnetic field, we detected additional splitting of the exciton peaks, indicating the coexistence of various orientations of Néel vector. This study characterizes orbital change of Zhang-Rice exciton and field-induced spin-reorientation phase transitions in a 2D hexagonal XY-type antiferromagnet, and it further demonstrates the continuous manipulation of the spin and polarization of the Zhang-Rice exciton. NiPS3 is a van der Waals antiferromagnet with a rich optical response including an exciton of very narrow linewidth, the origin of which is still a topic of active discussion. Herein, Song, Lv and coauthors study the response of the Zhang-Rice exciton to applied magnetic fields. [ABSTRACT FROM AUTHOR]

Efficient detection of the magnetic state is a critical step towards useful antiferromagnet-based spintronic devices. Recently, finite tunneling magnetoresistance (TMR) has been demonstrated in tunnel junctions with antiferromagnetic electrodes, however, these studies have been mostly limited to junctions with two identical antiferromagnet (AFM) electrodes, where the matching of the spin-split Fermi surfaces played critical role. It remains unclear if AFMs can provide a finite net spin polarization, and hence be used as a spin polarizer or detector. In this work, we experimentally fabricate single-sided antiferromagnetic tunnel junctions consisting of one AFM electrode (Mn3Sn) and one ferromagnet (FM) electrode (CoFeB), where the spin polarized tunneling transport from AFM is detected by the FM layer. We observe a high TMR at cryogenic temperature (>100% at 10 K) in these asymmetric AFM tunnel junctions, suggesting a large effective spin polarization from Mn3Sn despite its nearly vanishing magnetization. The large TMR is consistent with recent theoretical studies where the broken symmetry in non-collinear AFMs is predicted to lift the spin degeneracy in the band structure. Our work provides strong evidence that spin polarized electrical transport can be achieved from AFMs. Antiferromagnets have both negligible stray fields, and fast dynamics, making them ideal for fast and densely packed spintronic devices. However, readout of the antiferromagnet state is challenging. Here, Chou et al detect the spin-polarized current emanating from a noncollinear AFM, Mn3Sn. [ABSTRACT FROM AUTHOR]

Ab initio calculations based on density functional theory with the PBEsol method were utilized to examine the influence of hydrogen passivation, vacancies, and dopants on the electronic and magnetic properties of zigzag MgO nanoribbons with a width of w = 6 (6Z-MgONR). Calculations suggested that the 6Z-MgONR–2H configuration, which lacked magnetism and exhibited metallic characteristics, was the most stable configuration. Herein, this configuration with intrinsic defects and impurities were deeply considered. Finds revealed that individual VMg and VO vacancies induced magnetic moments of 0.624 μB and 0 μB, respectively. The calculated formation energy indicated that the occurrence of a single VMg was energetically favored than a single VO. Moreover, the three oxygen atoms adjacent to vacancy displayed inconsistent spin polarization directions, resulting in smaller magnetic moments than bulk MgO. Upon the introduction of Li or N impurities, LiMg under O-rich conditions exhibited the lowest formation energy. This was accompanied by an increase in total magnetic moments to 1.435 μB, which was significantly higher in the case of Mg vacancy. The corresponding spin-resolved charge density clearly demonstrated that the spin polarization was strongly localized at the right edge passivation of H atoms, with a minor contribution from the O atoms closest to the right edge H atoms. The NO/6Z-MgONR–2H configuration also exhibited total magnetic moments of 1.872 μB, but it had a substantially higher defect formation energy compared to the LiMg/6Z-MgONR–2H system. [ABSTRACT FROM AUTHOR]

The chip-scale hybrid optical pumping spin-exchange relaxation-free (SERF) atomic magnetometer with a single-beam arrangement has prominent applications in biomagnetic measurements because of its outstanding features, including ultrahigh sensitivity, an enhanced signal-to-noise ratio, homogeneous spin polarization and a much simpler optical configuration than other devices. In this work, a miniaturized single-beam hybrid optical pumping SERF atomic magnetometer based on a microfabricated atomic vapor cell is demonstrated. Although the optically thin Cs atoms are spin-polarized, the dense Rb atoms determine the experimental results. The enhanced signal strength and narrowed resonance linewidth are experimentally proven, which shows the superiority of the proposed magnetometer scheme. By using a differential detection scheme, we effectively suppress optical noise with an approximate five-fold improvement. Moreover, the cell temperature markedly affects the performance of the magnetometer. We systematically investigate the effects of temperature on the magnetometer parameters. The theoretical basis for these effects is explained in detail. The developed miniaturized magnetometer has an optimal magnetic sensitivity of 20 fT/Hz1/2. The presented work provides a foundation for the chip-scale integration of ultrahighly sensitive quantum magnetometers that can be used for forward-looking magnetocardiography (MCG) and magnetoencephalography (MEG) applications. [ABSTRACT FROM AUTHOR]

The free-field switching of the perpendicular magnetization by the out-of-plane polarized spin current induced spin-orbit torque makes it a promising technology for developing high-density memory and logic devices. The materials intrinsically with low symmetry are generally utilized to generate the spin current with out-of-plane spin polarization. However, the generation of the out-of-plane polarized spin current by engineering the symmetry of materials has not yet been reported. Here, we demonstrate that paramagnetic CaRuO3 films are able to generate out-of-plane polarized spin current by engineering the crystal symmetry. The non-uniform oxygen octahedral tilt/rotation along film's normal direction induced by oxygen octahedral coupling near interface breaks the screw-axis and glide-plane symmetries, which gives rise to a significant out-of-plane polarized spin current. This spin current can drive field-free spin-orbit torque switching of perpendicular magnetization with high efficiency. Our results offer a promising strategy based on crystal symmetry design to manipulate spin current and could have potential applications in advanced spintronic devices. The authors realize generation of out-of-plane polarized spin current in perovskite oxide CaRuO3 with reduced crystal symmetry by engineering the oxygen octahedra, which can drive efficient field-free switching of perpendicular magnetization. [ABSTRACT FROM AUTHOR]

Hyperpolarization has become a powerful tool to enhance the sensitivity of magnetic resonance. A universal tool to hyperpolarize small molecules in solution, however, has not yet emerged. Transferring hyperpolarized, labile protons between molecules is a promising approach towards this end. Therefore, hydrogenative parahydrogen-induced polarization (PHIP) was recently proposed as a source to polarize exchanging protons (PHIP-X). Here, we identified four key components that govern PHIP-X: adding the spin order, polarizing the labile proton, proton exchange, and polarization of the target nucleus. We investigated the last two steps experimentally and using simulations. We found optimal exchange rates and field cycling methods to polarize the target molecules. We also investigated the influence of spin relaxation of exchanging protons on the target polarization. It was found experimentally that transferring the polarization from protons directly bound to the target X-nucleus (here 13C) of lactate and methanol using a pulse sequence was more efficient than applying a corresponding sequence to the labile proton. Furthermore, varying the concentrations of the transfer and target molecules yielded a distinct maximum 13C polarization. We believe this work will further help to understand and optimize PHIP-X towards a broadly applicable hyperpolarization method. Hyperpolarization has become a powerful tool to enhance the sensitivity of NMR analyses, whereby hydrogenative parahydrogen-induced polarization with exchanging protons could broaden its applicability. Here, the authors identify four key components that govern the polarization of exchanging protons, and propose optimal exchange rates and field cycling methods to polarize target molecules. [ABSTRACT FROM AUTHOR]

In this work we investigate the spin-dependent transport through a double quantum dot embedded in a ferromagnetic tunnel junction and side attached to a topological superconducting nanowire hosting Majorana zero-energy modes. We focus on the transport regime when the Majorana mode leaks into the double quantum dot competing with the two-stage Kondo effect and the ferromagnetic-contact-induced exchange field. In particular, we determine the system's spectral properties and analyze the temperature dependence of the spin-resolved linear conductance by means of the numerical renormalization group method. Our study reveals unique signatures of the interplay between the spin-resolved tunneling, the Kondo effect and the Majorana modes, which are visible in the transport characteristics. In particular, we uncover a competing character of the coupling to topological superconductor and that to ferromagnetic leads, which can be observed already for very low spin polarization of the electrodes. This is signaled by an almost complete quenching of the conductance in one of the spin channels which is revealed through perfect conductance spin polarization. Moreover, we show that the conductance spin polarization can change sign depending on the magnitude of spin imbalance in the leads and strength of interaction with topological wire. Thus, our work demonstrates that even minuscule spin polarization of tunneling processes can have large impact on the transport properties of the system. [ABSTRACT FROM AUTHOR]

In the realm of multiferroicity in 2D magnets, whether magnetic and polar skyrmions can coexist within a single topological entity has emerged as an important question. Here, we study Janus 2D magnets CrInX3 (X=Se, Te) for a comprehensive investigation of the magnetic ground state, magnetic excited state, and corresponding ferroelectric polarization by first-principles electronic structure calculations and Monte Carlo simulations. Specifically, we have thoroughly elucidated the magnetic exchange mechanisms, and have fully exemplified the magnetic field dependence of the magnon spectrum. More importantly, our study reveals a previously unrecognized, remarkably large spin-spiral-induced ferroelectric polarization (up to 194.9 μC/m2) in both compounds. We propose an approach to identify polar skyrmions within magnetic skyrmions, based on the observed direct correlation between spin texture and polarization density. Elucidating this correlation not only deepens our understanding of magnetic skyrmions but also paves the way for innovative research in the realm of multiferroic skyrmions. [ABSTRACT FROM AUTHOR]

This research aims to employ a first-principles approach based on density functional theory (DFT) to predict the structural, electronic, and magnetic attributes of CdMX compounds, where M represents Ru , Rh , or Pd , and X represents either S or Se . We utilized the modified Beck-Johnson potential, combined with the generalized gradient approximation ( mBJGGA ), to scrutinize the electronic and magnetic features of these compounds. The results reveal robust magnetic ground states for M -doped CdX . The analysis of spin-polarized band structures and densities of states indicates that CdRuX and CdPdX compounds exhibit half-metallic ferromagnetism, characterized by complete spin polarization of 100% at the Fermi level. Conversely, CdRhX compounds exhibit the properties of ferromagnetic semiconductors. For Ru , Rh , and Pd -doped CdX , an integer-integrated total magnetic moment is observed, corresponding to 4, 3, and 2 μ B , respectively, with the primary contribution stemming from the doping atom and its four nearest neighboring X atoms. This ferromagnetic behavior is attributed to the strong p - d hybridization occurring between the states of the host X ions and the M impurity ion. Consequently, the outcomes of our study render these alloys as suitable materials for possible spintronic devices. [ABSTRACT FROM AUTHOR]

Context: The coherent electron/spin transport in azurin, a species of copper protein, was calculated based on the Landauer model. The research is motivated by the fast electron transport and spin selectivity/polarization in azurin, which have been reported in relation to the chiral-induced spin selectivity of the peptide structure. The calculated spin polarization of copper proteins was large. This phenomenon was strongly influenced by the spin density of the atoms in the ligand group, whereas the contribution of copper was negligible. The results suggest that spin polarization in copper proteins is enhanced by that of the ligand groups. The predicted spin polarization aligns primarily with the scanning tunneling microscope-based break-junction technique to study the electronic properties of single-molecule junctions. Methods: Computational techniques employed in this study are nonequilibrium Green's functions (NEGF) and density functional theory (DFT) based on the Landauer model, implemented using the QuantumATK software (Synopsys Inc.). The Perdew-Burke-Ernzerhof (PBE) exchange-correlation functional was adopted for spin-polarized generalized gradient approximation (SGGA). The valence atomic orbitals were constructed using the wavefunctions of the SIESTA package, which was based on the norm-conserving Troullier–Martins relativistic pseudopotentials for describing core electrons. The mesh used for real-space integration was 150 Ha. [ABSTRACT FROM AUTHOR]

Nowadays there is considerable interest in the photogalvanic effect in low-dimensional devices. In this work, we built a two-dimensional Bi2C-based photodetector and explored the spin-dependent photogalvanic effect under linearly polarized light and zero-bias conditions which can produce experimentally observable photoelectron flow. It was discovered that by introducing vacancies and substitution-doping into the Bi2C photodetector, the photogalvanic effect could be enhanced by 10–100 times that of a pristine photodetector, which is sufficient to be detected in experiments. Moreover, due to strong spin–orbit interactions, the Bi2C photodetector can produce very high spin polarization, even 100% full spin polarization, and pure spin current at a specific incident angle and photon energy, for example in the Bi1-vacancy Bi2C photodetector. In addition, the photon energy of incident light can regulate the produced spin photocurrent, which shows considerable anisotropy. Our results highlight the potential of the Bi2C photodetector as a versatile device in optoelectronics and spintronics applications. [ABSTRACT FROM AUTHOR]

A phase transition accompanied by the appearance of a spike in the longitudinal resistance of a two-dimensional electron system has been studied using the electron spin resonance near the filling factor ν = 3 in the ZnO/MgZnO heterojunction. This transition occurs when the tilt angle θ of the magnetic field is increased to some critical value θc. An analysis of the spin resonance amplitude has made it possible to demonstrate the spin nature of this phenomenon. For example, the ground state of the system on both sides of the transition has a nonzero spin polarization, which changes by several times when the phase of the system is changed. Strong spin resonance is observed both at θ < θc and at θ > θc. Surprisingly, the spin resonance at the critical angle θc has been detected in only one phase, which lies in the region of magnetic fields below the critical field Bc corresponding to the spike position in the longitudinal resistance. An increase in the magnetic field to this value leads to a decrease in the resonance amplitude and an increase in the resonance width. In the field region above Bc, the spin resonance disappears completely. Such behavior of the spin resonance is most likely due to the formation of domains with different spin polarizations in the electron system. [ABSTRACT FROM AUTHOR]

This study employs a first-principles approach to comprehensively examine the structural, electronic, optical, and magnetic properties of the thermodynamically stable scintillating double perovskite halides A 2 N a T a X 6 ( A = C s , R b ; X = C l , B r , I ). The dynamic stability of these materials were explained based on deduced phonon properties. Our analysis reveals that these compounds exhibit intriguing electronic behavior with spin polarization, demonstrating half-metallicity. In spin-up, the band gap is found to be zero, while in spin-down, it falls within the range of 3 to 4 eV with the incorporation of DFT+U corrections. Notably, the optical properties assessment highlights the exceptional UV and high-energy absorption capabilities of A 2 N a T a I 6 , making it a promising candidate for scintillation applications in particle detection. This research sheds light on the unique and versatile properties of these materials, with implications for various technological and scientific applications. [ABSTRACT FROM AUTHOR]

The oxygen evolution reaction, which involves high overpotential and slow charge-transport kinetics, plays a critical role in determining the efficiency of solar-driven water splitting. The chiral-induced spin selectivity phenomenon has been utilized to reduce by-product production and hinder charge recombination. To fully exploit the spin polarization effect, we herein propose a dual spin-controlled perovskite photoelectrode. The three-dimensional (3D) perovskite serves as a light absorber while the two-dimensional (2D) chiral perovskite functions as a spin polarizer to align the spin states of charge carriers. Compared to other investigated chiral organic cations, R-/S-naphthyl ethylamine enable strong spin-orbital coupling due to strengthened π–π stacking interactions. The resulting naphthyl ethylamine-based chiral 2D/3D perovskite photoelectrodes achieved a high spin polarizability of 75%. Moreover, spin relaxation was prevented by employing a chiral spin-selective L-NiFeOOH catalyst, which enables the secondary spin alignment to promote the generation of triplet oxygen. This dual spin-controlled 2D/3D perovskite photoanode achieves a 13.17% of applied-bias photon-to-current efficiency. Here, after connecting the perovskite photocathode with L-NiFeOOH/S-naphthyl ethylamine 2D/3D photoanode in series, the resulting co-planar water-splitting device exhibited a solar-to-hydrogen efficiency of 12.55%. Enhancing the efficiency of solar-driven water splitting is challenging but highly interesting. Here the authors report a dual spin-controlled 2D/3D perovskite photoelectrode that achieves 12.55% efficiency by utilizing the chiral-induced spin selectivity phenomenon. [ABSTRACT FROM AUTHOR]

The flat bands in magic-angle twisted bilayer graphene (MATBG) provide an especially rich arena to investigate interaction-driven ground states. While progress has been made in identifying the correlated insulators and their excitations at commensurate moiré filling factors, the spin-valley polarizations of the topological states that emerge at high magnetic field remain unknown. Here we introduce a technique based on twist-decoupled van der Waals layers that enables measurement of their electronic band structure and–by studying the backscattering between counter-propagating edge states–the determination of the relative spin polarization of their edge modes. We find that the symmetry-broken quantum Hall states that extend from the charge neutrality point in MATBG are spin unpolarized at even integer filling factors. The measurements also indicate that the correlated Chern insulator emerging from half filling of the flat valence band is spin unpolarized and suggest that its conduction band counterpart may be spin polarized. The hierarchy of symmetry breaking in magic-angle twisted bilayer graphene remains a topic of intense fundamental study. Here, the authors determine the spin polarization of symmetry-broken quantum Hall states and Chern insulators in MATBG using a twist-decoupled graphene probe. [ABSTRACT FROM AUTHOR]

The emergence of magnetic transition metal dichalcogenides has significantly advanced the development of valleytronics due to the spontaneous breaking of time-reversal symmetry and space-inversion symmetry. However, the lack of regulation methods has prevented researchers from exploring their potential applications. Herein, we propose to use strain engineering to control the spin-valley coupling in the sliding ferroelectric bilayer 2H-VX2 (X = S, Se, Te). Four multiferroic states are constructed by combining the sliding ferroelectricity and antiferromagnetism in the R-stacking bilayer VX2, where the spin and valley polarizations are coupled together from the layer-dependent spin-polarized band structures. By applying a small external strain or pressure on the out-of-plane van der Waals direction, we predicted that there is an antiferromagnetic to magnetic transition in the bilayer VX2, leading to the interesting spin-polarized and chiral circularly polarized radiation at K+ and K- valleys, similar to those found in the magnetic monolayer. To comprehend the coupling between various degrees of freedom in these multiferroic systems, we have developed an effective k·p model. This model unveils a linear relationship between the electric polarization generated by interlayer sliding and the energy difference of the valence band maximum at K+ and K- valleys. Thus, providing an alternate method to measure the electric polarization in the sliding ferroelectrics. Based on the strong coupling between the strain, spin-valley, and electric polarization, it is likely to use the strain to control the interesting emerging properties of 2H-VX2 such as the anomalous valley Hall effect. [ABSTRACT FROM AUTHOR]

Metabolism is a fundamental process that underlies human health and diseases. Nuclear magnetic resonance (NMR) techniques offer a powerful approach to identify metabolic processes and track the flux of metabolites at the molecular level in living systems. An in vitro study through in-cell NMR tracks metabolites in real time and investigates protein structures and dynamics in a state close to their most natural environment. This technique characterizes metabolites and proteins involved in metabolic pathways in prokaryotic and eukaryotic cells. In vivo magnetic resonance spectroscopy (MRS) enables whole-organism metabolic monitoring by visualizing the spatial distribution of metabolites and targeted proteins. One limitation of these NMR techniques is the sensitivity, for which a possible improved approach is through isotopic enrichment or hyperpolarization methods, including dynamic nuclear polarization (DNP) and parahydrogen-induced polarization (PHIP). DNP involves the transfer of high polarization from electronic spins of radicals to surrounding nuclear spins for signal enhancements, allowing the detection of low-abundance metabolites and real-time monitoring of metabolic activities. PHIP enables the transfer of nuclear spin polarization from parahydrogen to other nuclei for signal enhancements, particularly in proton NMR, and has been applied in studies of enzymatic reactions and cell signaling. This review provides an overview of in-cell NMR, in vivo MRS, and hyperpolarization techniques, highlighting their applications in metabolic studies and discussing challenges and future perspectives. [ABSTRACT FROM AUTHOR]

We experimentally investigate magnetization reversal curves for a GeTe topological semimetal. In addition to the known lattice diamagnetic response, we observe narrow magnetization loop in low fields, which should not be expected for non-magnetic material. The diamagnetic hysteresis loop is unusual, so the saturation level is negative in positive fields, and the loop is passed clockwise, in contrast to standard ferromagnetic behavior. We show, that the experimental hysteresis curves cannot be obtained from standard ferromagnetic ones by adding/subtracting of any linear dependence, or even by considering several interacting magnetic phases. The latter possibility is also eliminated by the remanence plots technique (Henkel or plots). We explain our results as a direct consequence of the correlation between ferroelectricity and spin-polarized surface states in GeTe, similarly to magnetoelectric structures. [ABSTRACT FROM AUTHOR]

Emergent phenomena such as two-dimensional electron gas (2DEG) and interfacial superconductivity and ferromagnetism are generally built on the interface between insulating oxide thin films and substrates, e.g., LaAlO3/SrTiO3, where the 2D profiles of these electronic states are precisely confined at the interface of two insulators. Herein we report a high-mobility electron gas state with unusual symmetry at the interface of the Sr2CrMoO6/SrTiO3 (110) heterostructures, the fermiology of which follows the cubic crystallographic symmetry rather than the two-dimensional interface itself, resulting in the identical Shubnikov-de Haas oscillations with applied magnetic field along all the twelve equivalent [110] crystallographic directions of SrTiO3, distinctly different from the 2D nature of the electron gas reported previously. Neutron diffraction verifies the predicted ferrimagnetic ordering between Cr and Mo moments. This, together with the magnetic hysteresis loops and negative magnetoresistance in low-field region, suggests possible spin polarization of itinerant electrons. Therefore, a quasi-3D profile, high mobility (up to 104 cm2 V−1 s−1) and possibly spin polarized electronic state is observed in the double-perovskite-based oxide heterostructures. This finding of the electronic properties in Sr2CrMoO6/SrTiO3 (110) heterostructure expands the knowledge of interfacial physics, as well as shines light on oxide-based electronics and spintronics research. The existence of electron gas at the interfaces of oxide-based heterostructures with broken spatial inversion symmetry gives rise to various interesting physical phenomena. Here, the authors report a new type quasi-three-dimensional electron gas state at the interface of ferrimagnetic semiconductor-strontium titanate heterostructures, which show high mobility, high valley degeneracy and possible spin polarization. [ABSTRACT FROM AUTHOR]

Polarization and spin correlations have been studied in detail for top quarks at the LHC, but have been explored very little for the other flavors of quarks. In this paper we consider the processes pp → with q = b, c or s. Utilizing the partial preservation of the quark's spin information in baryons in the jet produced by the quark, we examine possible analysis strategies for ATLAS and CMS to measure the quark polarization and spin correlations. We find polarization measurements for the b and c quarks to be feasible, even with the currently available datasets. Spin correlation measurements for are possible using the CMS Run 2 parked data, while such measurements for will become possible with higher integrated luminosity. For the s quark, we find the measurements to be challenging with the standard triggers. We also provide leading-order QCD predictions for the polarization and spin correlations expected in the and samples with the cuts envisioned for the above analyses. Apart from establishing experimentally the existence of spin correlations in and systems produced in pp collisions, the proposed measurements can provide new information on the polarization transfer from quarks to baryons and might even be sensitive to physics beyond the Standard Model. [ABSTRACT FROM AUTHOR]

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

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The spin Hall effect (SHE) allows efficient generation of spin polarization or spin current through charge current and plays a crucial role in the development of spintronics. While SHE typically occurs in non-magnetic materials and is time-reversal even, exploring time-reversal-odd (T-odd) SHE, which couples SHE to magnetization in ferromagnetic materials, offers a new charge-spin conversion mechanism with new functionalities. Here, we report the observation of giant T-odd SHE in Fe3GeTe2/MoTe2 van der Waals heterostructure, representing a previously unidentified interfacial magnetic spin Hall effect (interfacial-MSHE). Through rigorous symmetry analysis and theoretical calculations, we attribute the interfacial-MSHE to a symmetry-breaking induced spin current dipole at the vdW interface. Furthermore, we show that this linear effect can be used for implementing multiply-accumulate operations and binary convolutional neural networks with cascaded multi-terminal devices. Our findings uncover an interfacial T-odd charge-spin conversion mechanism with promising potential for energy-efficient in-memory computing. Charge-to-spin conversion allows for the generation and control of spin polarization via a charge current. Typically, this is done with non-magnetic materials with large spin-orbit interactions such as Platinum. Herein, Dai et al demonstrate an intriguing charge-to-spin mechanism, a magnetic spin Hall effect, in a van der Waals heterostructure. [ABSTRACT FROM AUTHOR]

With the field correlator method (FCM) for QCD, we show that the chiral vortical effect (CVE) in hot (strongly-interacting) quark-gluon plasma ((s)QGP) is modified by non-perturbative interactions – by color-magnetic confinement, and by remnant color-electric interaction, which is encoded in the Polyakov line. The obtained result demonstrates numerical suppression of CVE comparable to the phenomenological suppression used for numerical simulations of RHIC-STAR data on hyperons spin polarization in non-central heavy ion collision (HIC). The parameters range in the temperature – quark chemical potential plane is expected to cover ALICE and RHIC data. The chiral current is calculated for the rigidly rotating model of (s)QGP in the linear order in angular velocity at the rotation axis with account of non-perturbative interactions. [ABSTRACT FROM AUTHOR]

We have looked at a very interesting class of Heusler alloy that has received a lot of theoretical research but a very little experimental attention. Mn2TiSi Heusler alloy was synthesized by a conventional vacuum arc remelting process. The formation of Heusler phase along with the secondary phases was observed after annealing it at 773 K for 120 h. The X-ray diffraction pattern illustrates the presence of cubic B2 disordered phase along with a secondary phase with a lattice parameter of 5.82 Å. The microstructure and compositional analysis of Mn2TiSi alloy shows the presence of distribution of Mn, Ti, and Si elements according to their stoichiometric ratio. The magnetic measurements show a ferromagnetic nature with Curie temperature (TC) around 203 K. With low magnetic moment and coercivity, Mn2TiSi can be used for switching applications because of its fast magnetization reversal. So, Mn2TiSi becomes the greatest choice for use in spintronics due to its low magnetic moment and low coercivity. [ABSTRACT FROM AUTHOR]

Electret fiber filtration materials prepared by electrostatic spinning and corona polarization have drawn significant interest in treating radioactive aerosols. In this study, a three-dimensional biomass-based electret nanofiber aerogel material with high dust capacity, high filtration efficiency and low-pressure drop was created by pore structure regulation. The results showed that aerogels with good charge capture and storage ability were obtained by regulating the concentration of tert-butanol and ethylcellulose fiber suspension, and the pre-freezing temperature. The initial surface potential and stable surface potential increased from 0.85 and 0.05 kV to 1.37 and 0.15 kV respectively. Furthermore, the purification time was reduced from 44 to 15 min. [ABSTRACT FROM AUTHOR]

We investigate plasmon properties in a double-layer graphene structure under the effects of an in-plane external magnetic field within the zero-temperature random-phase approximation. Numerical calculations demonstrate that two plasmon modes exist in the system, corresponding to in-phase and out-of-phase oscillations of charges. The spin polarization number P affects the optical and acoustic plasmon modes and their decay rate differently. As the polarization number increases, the frequency of the acoustic mode slightly decreases while that of the optical mode significantly increases. Besides, the existence of an external magnetic field expands the single-particle-excitation area of the system; therefore, plasmon modes become damped at a smaller wave vector, compared to those in the case of unpolarized systems. The separation between two layers increases (decreases) the plasmon frequency of the acoustic (optical) mode. Finally, we found that background dielectric inhomogeneity decreases the energy and decay rate of plasmon modes of the spin-polarized system. [ABSTRACT FROM AUTHOR]