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Chiral-induced-spin-selectivity of electron transport and its interplay with DNA's mechanical motion are explored in a double stranded DNA helix with spin–orbit-coupling. The mechanical degree of freedom is treated as a stochastic classical variable experiencing fluctuations and dissipation induced by the environment as well as force exerted by nonequilibrium, current-carrying electrons. Electronic degrees of freedom are described quantum mechanically using nonequilibrium Green's functions. Nonequilibrium Green's functions are computed along the trajectory for the classical variable taking into account dynamical, velocity dependent corrections. This mixed quantum-classical approach enables calculations of time-dependent spin-resolved currents. We showed that the electronic force may significantly modify the classical potential, which, at sufficient voltage, creates a bistable potential with a considerable effect on electronic transport. The DNA's mechanical motion has a profound effect on spin transport; it results in chiral-induced spin selectivity, increasing spin polarization of the current by 9% and also resulting in temperature-dependent current voltage characteristics. We demonstrate that the current noise measurement provides an accessible experimental means to monitor the emergence of mechanical instability in DNA motion. The spin resolved current noise also provides important dynamical information about the interplay between vibrational and spin degrees of freedom in DNA. [ABSTRACT FROM AUTHOR]

This study delves into the interplay of symmetry and structure in 2D systems to identify monolayers hosting valley physics together with the Rashba effect. Through high-throughput density functional theory calculations, 57 monolayers are identified exhibiting the Rashba effect, with the Rashba parameter α R spanning from 0 < α R < 2.0. The robustness of the Rashba parameters (α R) in these monolayers is primarily influenced by the physical parameters, highlighting the anti-crossing of Rashba-split bands and the Born effective charge (Z*). Among the 57 monolayers exhibiting the Rashba effect, the study identifies a subset of 23 monolayers presenting valley physics, demonstrating both in-plane and out-of-plane spin polarizations. The pronounced coupling of the valley and Rashba spin splitting is influenced by the in-plane and out-of-plane orbital contributions at the relevant K-points in the band spectra. In particular, the AB-type buckled structures feature these dual properties due to the presence of the broken inversion and mirror symmetries in them. Overall, the study eases the identification of monolayers with significant spin splitting and spin polarization, aiding in the design of high-performance 2D materials. [ABSTRACT FROM AUTHOR]

Chiral structures, breaking spatial inversion symmetry, exhibit non-zero chiroptical activity (COA) due to the coupling between their electric and magnetic responses under external electromagnetic fields, an effect absent in achiral systems. Non-magnetic chiral structures also exhibit Chiral-Induced Spin Selectivity (CISS), primarily detected in two terminal measurements in the linear regime, where spin selection emerges without external magnetic influence. Despite the different origins of these physical phenomena, our model captures the relevant physics required to address CISS as an intrinsic molecular effect with the basic ingredients: (i) chirality/inversion asymmetry, (ii) meV atomic spin–orbit coupling, and (iii) decoherence as a source of reciprocity breaking. In this work, we derived how the electronic system couples with polarized electromagnetic radiation to yield a spin-dependent polarization rotation power, quantified through the Rosenfeld tensor, predicting characteristic spin signatures in the COA. The model also predicts that a net spin polarization manifests in the molecular terminations that have been surmised as an explanation for chiral species separation of racemic mixtures and interactions with surface magnetic domains. A recent sensitive spectroscopic measurement of electron transfer in donor–acceptor complexes is consistent with the standalone CISS effect. [ABSTRACT FROM AUTHOR]

This study reports light narrowing in paraffin-coated vapor cells from room temperature 27 to 59 °C, where spin-exchange relaxation is suppressed. By means of a coating lock and eliminating the reservoir effect, an ultra-narrow magnetic resonance linewidth of 0.36 Hz and an atomic coherence lifetime of T 2 = 0.9 s are achieved. In cells free of buffer gas, the narrow linewidth over this broad temperature range is a result of enhanced spin polarization, which is facilitated by the effective suppression of radiation trapping benefiting from the stability of the vapor density. Using such cells in atomic magnetometers, the photon shot noise limit is estimated as 0.2 fT / Hz 1 / 2 and the spin-projection noise limit is estimated as 1.1 fT / Hz 1 / 2 . Also, a magnetometer system with the stable coated cell is identified, which demonstrates the potential for achieving relatively stable magnetometer sensitivity without precisely controlling the cell temperature. The long coherence lifetime and the broad operating temperature range expand the potential applications of quantum memory and other quantum sensors such as atomic clocks. [ABSTRACT FROM AUTHOR]

We have observed a transition from single to double hysteresis of nuclear spin polarization (NSP) with increasing magnetic field in a single InAlAs self-assembled quantum dot, which means the birth of a third stable branch that depends on the field strength. This NSP transition behavior could not be reproduced by standard model calculations using a fixed electron–nuclear spin correlation time τ c under different external field conditions. By introducing the field dependence of τ c , we were able to successfully reproduce the observed NSP transition. This finding on the phenomenological description of the magnetic field dependence will be a future highlight of τ c . [ABSTRACT FROM AUTHOR]

The second-order nonlinear Hall effect in 8-Pmmn monolayer borophene under the influence of an out-of-plane electric field and intrinsic spin–orbit interaction is reported. This unconventional response sensitive to the breaking of discrete and crystal symmetries can be tuned by the applied electric field, which can vary the bandgap induced by spin–orbit coupling. It is described by a Hall conductivity tensor that depends quadratically on the applied electric field. We find that the nonlinear Hall effect strongly depends on the spin polarization. In particular, it exhibits out of the phase character for spin-up and spin-down states. Remarkably, it undergoes a phase flip in the spin-up state at a large out-of-plane electric field that generates a staggered sublattice potential greater than the spin–orbit interaction strength. It is shown that the nonlinear Hall effect in the system originates from the broken inversion symmetry that plays an indispensable role in developing finite Berry curvature and its relevant dipole moment. It is found that at zero temperature, the nonlinear Hall response is maximal when the Fermi energy is twice the bandgap parameter and vanishes at large Fermi energies. Notably, the peak of nonlinear Hall response shifts to lower Fermi energies at finite temperature. [ABSTRACT FROM AUTHOR]

High-performance and stable spintronic devices have garnered considerable attention in recent years. Based on first-principle and Monte Carlo calculations, we demonstrate that under reasonable carrier doping, H-VSe2 exhibits 100% spin polarization, a magnetic anisotropy energy of 581 μeV, a tunable easy-axis, and a Curie temperature of 330 K. Moreover, Dzyaloshinskii–Moriya interactions in H-VSe2 and magnetic hysteresis loops are determined theoretically for the first time, which provides more precise and comprehensive descriptions of its magnetic properties under finite temperatures and external magnetic field. This work suggests that H-VSe2 is a powerful candidate for spintronic devices, and it provides solid theoretical support for future experiments. [ABSTRACT FROM AUTHOR]

The interactions between the electronic magnetic moment and the nuclear spin moment, i.e., magnetic hyperfine (HF) interactions, play an important role in understanding electronic properties of magnetic systems and in realizing platforms for quantum information science applications. We investigate the HF interactions for atomic systems and small molecules, including Ti or Mn, by using Fermi–Löwdin orbital (FLO) based self-interaction corrected (SIC) density-functional theory. We calculate the Fermi contact (FC) and spin-dipole terms for the systems within the local density approximation (LDA) in the FLO-SIC method and compare them with the corresponding values without SIC within the LDA and generalized-gradient approximation (GGA), as well as experimental data. For the moderately heavy atomic systems (atomic number Z ≤ 25), we find that the mean absolute error of the FLO-SIC FC term is about 27 MHz (percentage error is 6.4%), while that of the LDA and GGA results is almost double that. Therefore, in this case, the FLO-SIC results are in better agreement with the experimental data. For the non-transition-metal molecules, the FLO-SIC FC term has the mean absolute error of 68 MHz, which is comparable to both the LDA and GGA results without SIC. For the seven transition-metal-based molecules, the FLO-SIC mean absolute error is 59 MHz, whereas the corresponding LDA and GGA errors are 101 and 82 MHz, respectively. Therefore, for the transition-metal-based molecules, the FLO-SIC FC term agrees better with experiment than the LDA and GGA results. We observe that the FC term from the FLO-SIC calculation is not necessarily larger than that from the LDA or GGA for all the considered systems due to the core spin polarization, in contrast to the expectation that SIC would increase the spin density near atomic nuclei, leading to larger FC terms. [ABSTRACT FROM AUTHOR]

Magnetic materials with high negative spin polarization have been sought as a building block to increase the design freedom and performance of spintronics devices. In this paper, we investigate negative spin polarization of Mn2VGa Heusler alloy in current-perpendicular-to-plane giant magnetoresistance (CPP-GMR) devices. We fabricated an epitaxial CPP-GMR stack consisting of Mn2VGa/Ag/CoFe with L21 ordering in the Mn2VGa layer and observed negative magnetoresistance (MR), which provided evidence of negative spin polarization. The MR ratio depended on thermal treatments (deposition at an elevated temperature and post-annealing), because these processes affected the ordering, roughness, and magnetic properties of Mn2VGa. The maximum MR ratio reached −1.8% at room temperature and −3.0% at low temperatures, representing the highest among the negative MR values in pseudo-spin-valve CPP-GMR devices despite the underestimation due to an incomplete antiparallel magnetization configuration. These findings demonstrate the potential of Mn2VGa for a material with high negative spin polarization. [ABSTRACT FROM AUTHOR]

Understanding the electronic transport properties of low-dimensional devices has increased dramatically in recent decades, especially for those with a promising future for application in nanotechnology. Among these nanoscopic systems are molecular systems, particularly organic molecules such as catechol, representing the small piece of a potential conductor assembled through larger biomolecules and inserted between two or more metal contacts. In this work, we present a theoretical description of the electronic transport of catechol, based on its π -conjugated aromatic system, under an external magnetic field stimulus, which is transverse to the alignment of the molecule. Thus, we analyze catechol's spintronic properties through the magnetoresistance generated by this field. We model the molecule using a tight-binding Hamiltonian and Green's functions; the transmission probability is calculated by means of the Fisher-Lee relation, and the characteristic current–voltage, spin polarization, and magnetoresistance curves based on Landauer's approach for two linking models of catechol to the metallic contacts. The results suggest a strong dependence on the spin direction of the charge carriers and the Zeeman energy (E z) on the Fermi level, generating a switch-like mechanism going from conducting to semiconducting material. This behavior opens a potential application of these catechol-based systems in future spintronic devices. [ABSTRACT FROM AUTHOR]

Chiral molecules can exhibit strong spin–orbit coupling, which can result in a large spin polarization. This is due to the fact that the energy levels of the electrons in a chiral molecule are strongly influenced by the chiral structure of the molecule, which can result in the separation of the energy levels for electrons with different spin orientations. We report a controlled spin-selective transmission of electrons through 20 base-paired poly-cytosine molecules functionalized with MoS2 flakes on ITO glass via the quantum mechanical tunneling effect. A reversion in spin polarization was observed after the silver ions interact with poly-cytosine due to the strong coordination of Ag(I) with cytosine–cytosine (C–C) mismatches, indicating the formation of duplex structural motifs, as confirmed by the circular dichroism spectroscopy at room temperature. Manipulating the spin of an electron through such a small molecule merely controlled by special cations could pave the way for major advances in spin-independent charge transport, advanced bioanalytical system design, and related applications. [ABSTRACT FROM AUTHOR]

We theoretically study the magnetic phase transition of condensed exciton-polariton microcavities in an applied magnetic field. When the magnetic field is strong, all polariton spins are polarized parallel to the magnetic field as usual. On the contrary, in the weak magnetic-field region, the polariton polarization degree is negative, namely, anti-parallel to the magnetic field. For a strong magnetic field, the magnetic phase of the polaritons arises and leads to a paramagnetic, while around a weak magnetic field, with zero exciton–photon detunings, and weak Rabi splitting the spin polarization of the polaritons leads to a diamagnetic. Thus, magneto-polariton phase transition polarization originates from the competition between the polariton Zeeman effect and polariton–polariton interactions. Moreover, the polariton polarization strongly depends on the exciton–photon detuning and Rabi splitting and has a large negative value as they are both small. At last, we compare our theoretical results with the experiments and find they match each other very well. [ABSTRACT FROM AUTHOR]

Chiral molecules can exhibit strong spin–orbit coupling, which can result in a large spin polarization. This is due to the fact that the energy levels of the electrons in a chiral molecule are strongly influenced by the chiral structure of the molecule, which can result in the separation of the energy levels for electrons with different spin orientations. We report a controlled spin-selective transmission of electrons through 20 base-paired poly-cytosine molecules functionalized with MoS2 flakes on ITO glass via the quantum mechanical tunneling effect. A reversion in spin polarization was observed after the silver ions interact with poly-cytosine due to the strong coordination of Ag(I) with cytosine–cytosine (C–C) mismatches, indicating the formation of duplex structural motifs, as confirmed by the circular dichroism spectroscopy at room temperature. Manipulating the spin of an electron through such a small molecule merely controlled by special cations could pave the way for major advances in spin-independent charge transport, advanced bioanalytical system design, and related applications. [ABSTRACT FROM AUTHOR]

In connection to the chiral-induced spin selectivity effect, we theoretically analyze the electronic and spin states of edges of a finite p-orbital helical atomic chain with the intra-atomic spin–orbit interaction. This model can host the spin-filtering state in which two up-spins propagate in one direction and two down-spins propagate in the opposite direction without breaking the time-reversal symmetry (TRS). The enhancement of charge modulations concentrated at the edges due to the evanescent states is induced, although the spin density is absent because of the TRS. A Zeeman field at an edge of the atomic chain, which breaks the TRS, yields a finite spin polarization, whose direction depends on the chirality of the molecule. The chirality change induces a reasonable amount of the energy difference, which may provide an insight into the enantioselective adsorption of chiral molecules on the ferromagnetic surface. [ABSTRACT FROM AUTHOR]

Enantio-discrimination and spin-dependent electrochemistry (SDE), as a manifestation of the chirality-induced spin selectivity (CISS) effect, are important phenomena that can be probed by "chiral" electrochemistry. Here, we prepared chiralized surfaces of gold and nickel, to serve as working electrodes, through effective chemisorption of enantiopure dimethyl-bis(ethylenedithio)-tetrathiafulvalene (DM-BEDT-TTF) 1, tetramethyl-bis(ethylenedithio)-tetrathiafulvalene (TM-BEDT-TTF) 2, and their capped silver nanoparticle (AgNPs) aggregate by simple incubation of the metallic substrates. The effective chemisorption was checked by means of ultrahigh vacuum x-ray photoelectron spectroscopy (XPS) and by electro-desorption experiments, i.e., cyclic voltammetry (CV) scans showing a first electro-desorption peak at about −1.0 V. The Au|1 and Au|2 chiral electrodes were successfully used in CV experiments exploiting chiral redox probes. Finally, the hybrid interfaces Ni|enantiopure 1 or 2|AgNPs served as working electrodes in SDE experiments. In particular, the hybrid chiral interfaces Ni|(R)-2|AgNPs and Ni|(S)-2|AgNPs exhibited a significant spin-filtering ability, as a manifestation of the CISS effect, with average spin polarization values of 15%. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the spin transport properties of binuclear manganese phthalocyanine (M n 2 P c 2) spintronic devices sandwiched between two nickel electrodes using the non-equilibrium Green's function method in combination with density functional theory. Based on the calculation results, the M n 2 P c 2 device exhibited excellent spin-filtering capabilities, demonstrating an exceptionally high spin filter efficiency (SFE). Irrespective of the parallel or antiparallel orientation of magnetization in the electrodes, we observed that when both manganese atoms were in a spin-up state, the SFE of spin-resolved currents under finite bias and the thermoelectric currents induced by temperature gradients at fixed temperatures were both close to 100%. The large spin Seebeck polarization of the M n 2 P c 2 device was also obtained at low reference temperatures. This study explores the potential for developing multifunctional spintronic single-molecule devices using Ni − M n 2 P c 2. [ABSTRACT FROM AUTHOR]

We report on a strategy to indirectly read out the spectrum of an electronic spin via polarization transfer to nuclear spins in its local environment. The nuclear spins are far more abundant and have longer lifetimes, allowing for repeated polarization accumulation in them. Subsequent nuclear interrogation can reveal information about the electronic spectral density of states. We experimentally demonstrate the method by reading out the ESR spectrum of nitrogen vacancy center electrons in diamond via readout of lattice 13C nuclei. Spin-lock control on the 13C nuclei yields a significantly enhanced signal-to-noise ratio for the nuclear readout. Spectrally mapped readout presents operational advantages in being background-free and immune to crystal orientation and optical scattering. We harness these advantages to demonstrate applications in underwater magnetometry. The physical basis for the "one-to-many" spectral map is itself intriguing. To uncover its origin, we develop a theoretical model that maps the system dynamics, involving traversal of a cascaded structure of Landau–Zener anti-crossings, to the operation of a tilted "Galton board." This work points to new opportunities for "ESR-via-NMR" in dilute electronic systems and in hybrid electron–nuclear quantum memories and sensors. [ABSTRACT FROM AUTHOR]

Chiral molecules can act as spin filters, preferentially transmitting electrons with spins polarized along their direction of travel, an effect known as chirality-induced spin selectivity (CISS). In a typical experiment, injected electrons tunnel coherently through a layer of chiral material and emerge spin-polarized. It is also possible that spin polarization arises in radical pairs formed photochemically when electrons hop incoherently between donor and acceptor sites. Here we aim to identify the magnetic properties that would optimise the visibility of CISS polarization in time-resolved electron paramagnetic resonance (EPR) spectra of transient radical pairs without the need to orient or align their precursors. By simulating spectra of actual and model systems, we find that CISS contributions to the polarization should be most obvious when at least one of the radicals has small g-anisotropy and an inhomogeneous linewidth larger than the dipolar coupling of the two radicals. Under these conditions there is extensive cancellation of absorptive and emissive enhancements making the spectrum sensitive to small changes in the individual EPR line intensities. Although these cancellation effects are more pronounced at lower spectrometer frequencies, the spectral changes are easier to appreciate with the enhanced resolution afforded by high-frequency EPR. Consideration of published spectra of light-induced radical pairs in photosynthetic bacterial reaction centres reveals no significant CISS component in the polarization generated by the conventional spin-correlated radical pair mechanism. [ABSTRACT FROM AUTHOR]

We present computational results on electronic, magnetic, and structural properties of CoVMnSb, a quaternary Heusler alloy. Our calculations indicate that this material may crystallize in two energetically close structural phases: inverted and regular cubic. The inverted cubic phase is the ground state, with ferrimagnetic alignment, and around 80% spin polarization. Despite having a relatively large bandgap in the minority-spin channel close to the Fermi level, this phase does not undergo a half-metallic transition under pressure. This is explained by the "pinning" of the Fermi level at the minority-spin states at the Γ point. At the same time, the regular cubic phase is half-metallic and retains its perfect spin polarization under a wide range of mechanical strain. Transition to a regular cubic phase may be attained by applying uniform pressure (but not biaxial strain). In practice, this pressure may be realized by an atomic substitution of non-magnetic atoms (Sb) with another non-magnetic atom (Si) of a smaller radius. Our calculations indicate that 25% substitution of Sb with Si results in a half-metallic regular cubic phase being the ground state. In addition, CoVMnSb0.5Si0.5 retains its half-metallic properties under a considerable range of mechanical pressure, as well as exhibits thermodynamic stability, thus making this alloy attractive for potential spintronic applications. We hope that the presented results will stimulate experimental efforts to synthesize this compound. [ABSTRACT FROM AUTHOR]

Repeatable hyperpolarization of high concentrations of mobile protons (>6 M) using parahydrogen in protic methanol/water mixtures is reported here. Different ammonium buffers with increasing mobile proton concentrations were added to an IrCl(COD)(IMes) catalyst in the presence of pyridine. We reach a maximum molar polarization of 1.79 mM at 6 mT. Field-cycling experiments in an 18.8 T detection field distinguished two solvent polarization transfer pathways: chemical exchange with labile protons from ammonia and cross-relaxation with pyridine aromatic protons. [ABSTRACT FROM AUTHOR]

We uncover a superconducting state with partial spin polarization induced by a magnetic field. This state, which we call "magnonic superconductor," lacks a conventional pairing order parameter but is characterized instead by a composite order parameter that represents the binding of electron pairs and magnons. We rigorously demonstrate the existence of magnonic superconductivity with high transition temperature in one-dimensional and two-dimensional Hubbard models with repulsive interaction. We further show that magnonic Cooper pairs can attract to form higher-charge bound states, which can give rise to charge-6e superconductivity. [ABSTRACT FROM AUTHOR]

Ferromagnets with high spin polarization are known to be valuable for spintronics—a research field that exploits the spin degree of freedom in information technologies. Recently, antiferromagnets have emerged as promising alternative materials for spintronics due to their stability against magnetic perturbations, absence of stray fields, and ultrafast dynamics. For antiferromagnets, however, the concept of spin polarization and its relevance to the measured electrical response are elusive due to nominally zero net magnetization. Here, we define an effective momentum-dependent spin polarization and reveal an unexpected property of many noncollinear antiferromagnets to exhibit nearly 100% spin polarization in a broad area of the Fermi surface. This property leads to the emergence of an extraordinary tunneling magnetoresistance (ETMR) effect in antiferromagnetic tunnel junctions (AFMTJs). As a representative example, we predict that a noncollinear antiferromagnet Mn3GaN exhibits nearly 100% spin-polarized states that can efficiently tunnel through low-decay-rate evanescent states of perovskite oxide SrTiO3 resulting in ETMR as large as 104%. Our results uncover hidden functionality of material systems with noncollinear spin textures and open new perspectives for spintronics. In most collinear antiferromagnets, PT symmetry leads to a lack of spin-polarization. Here, Gurung et al show that a noncollinear antiferromagnets can exhibit an extremely high degree of spin polarization over a large area of its Fermi surface and propose using this feature for the development of antiferromagnetic magnetic tunnel junctions. [ABSTRACT FROM AUTHOR]

Current induced spin–orbit torque (SOT) manipulation of magnetization is pivotal in spintronic devices. However, its application for perpendicular magnetic anisotropy magnets, crucial for high‐density storage and memory devices, remains nondeterministic and inefficient. Here, a highly efficient approach is demonstrated to generate collinear spin currents by artificial modulation of interfacial symmetry, achieving 100% current‐induced field‐free SOT switching in CoFeB multilayers with perpendicular magnetization on stepped Al2O3 substrates. This field‐free switching is primarily driven by the out‐of‐plane anti‐damping SOT generated by the planar spin Hall effect (PSHE), resulting from reduced interface symmetry due to orientation‐determined steps. Microscopic theoretical analysis confirms the presence and significance of PSHE in this process. Notably, this method for generating out‐of‐plane spin polarization along the collinear direction of the spin‐current with artificial modulation of interfacial symmetry, overcomes inherent material symmetry constraints. These findings provide a promising avenue for universal control of spin–orbit torque, addressing challenges associated with low crystal symmetry and highlighting its great potential to advance the development of energy‐efficient spintronic devices technology. [ABSTRACT FROM AUTHOR]

Magnetic memory based on spin‐orbit torque (SOT) is a promising candidate for the next‐generation storage devices. Materials that generate out‐of‐plane spin polarization (σz) are highly desired and actively pursued as the SOT generator, due to its ability to achieve field‐free SOT switching of perpendicular magnetization. However, integrating σz into perpendicular magnetic tunnel junction for efficient data writing is not realized. Here, utilizing σz from antiferromagnetic spin Hall effect in Mn2Au, σz‐enabled field‐free SOT switching of perpendicular magnetic tunnel junctions is realized demonstrating a magnetic memory with both writing and reading electrically. The tunnel magnetoresistance ratio achieves 66% with a critical current density of 5.6 × 106 A cm−2 at room temperature. Such field‐free fully SOT switching is further directly confirmed by domain imaging via magneto‐optical Kerr effect microscopy. In addition to enabling field‐free switching, σz is proposed to assist ultrafast and more efficient switching of perpendicular magnetization compared with conventional in‐planes ones, based on simulations. This research advances the application of out‐of‐plane SOTs and paves the way for high‐density, high‐speed, and low‐power magnetic memory. [ABSTRACT FROM AUTHOR]

Antiferromagnetic magnons possess a distinctive feature absent in their ferromagnetic counterparts: the presence of two distinct handedness modes, the right-handed (RH) and left-handed (LH) precession modes. The magnon handedness determines the sign of spin polarization carried by the propagating magnon, which is indispensable for harnessing the diverse functionalities in magnonic devices, such as data encoding, magnon polarization-based logic systems, and quantum applications involving magnons. However, the control of coherently propagating magnon handedness in antiferromagnets has remained elusive. Here we demonstrate the manipulation and electrical readout of propagating magnon handedness in perpendicularly magnetized synthetic antiferromagnets (SAF). We find that the antiferromagnetic magnon handedness can be directly identified by measuring the inverse spin Hall effect (ISHE) voltage, which arises from the spin pumping effect caused by the propagating antiferromagnetic magnons in the SAF structure. The RH and LH modes of the magnon can be distinguishable when the SAF structure is sandwiched by heavy metals with the same sign of spin Hall angle. This work unveils promising avenues for harnessing the unique properties of antiferromagnetic magnons. Antiferromagnetic magnons have two distinct chiralities, left handed and right handed. Here, Shiota and coauthors demonstrate both the manipulation and electrical readout of this handedness in a synthetic antiferromagnet. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) van der Waals antiferromagnetic (AFM) materials boast exceptional properties for spintronics, including high spin-wave speeds and negligible stray fields. Their layer-by-layer assembly into heterostructures enables the exploration of next-generation spintronic devices. However, most 2D AFM materials are semiconductors or insulators. Thus, magneto-transport, a key segment of spintronics, is difficult to obtain especially at low temperatures. Herein, we report the observation of anomalous Hall effect (AHE) in 2D CrOCl/Pt bilayer heterostructure. Magneto-transport measurements supported by density functional theory calculations reveal that the appearance of AHE is generated by spin polarization in Pt due to the magnetic proximity effect. In addition, it is demonstrated that the magnetic easy-axis changes from the z-axis to the xy-plane at the interface of the heterostructure. Our work sheds light on the magneto-transport properties of 2D CrOCl and its potential in emerging spintronic devices. [ABSTRACT FROM AUTHOR]

Using low and optimized magnetic field along with electric field is a novel strategy to facilitate electrochemical nitrite reduction reaction (NO2RR). Herein, the magnetic field assisted electrocatalytic ammonia synthesis employing spin‐thrusted β‐MnPc at 95 mT magnetic field is explored. The calculated rate of ammonia generation is 16603.4 µg h−1 mgcat−1, which is almost twice that of the nonpolarized manganese phthalocyanine (MnPc) catalyst. Additionally, the Faradaic efficiency (FE) at –0.9 V versus RHE is found to be 92.9%, significantly higher compared to the nonpolarized MnPc catalyst. In presence of external magnetic field, MnPc catalysts provide a better electron transfer channel which results in a lower charge transfer resistance and hence better electrochemical performances. Density functional theory (DFT) result further verifies that magnetic field induced β‐MnPc has a lower potential barrier (0.51 eV) for the protonation of NO* than nonpolarized β‐MnPc (1.08 eV), which confirms the enhanced electrochemical nitrite reduction to ammonia. [ABSTRACT FROM AUTHOR]

Ru‐based pyrochlores (e.g. Y2Ru2O7−δ) are promised to replace IrO2 in polymer electrolyte membrane (PEM) electrolyzers. It is significant to reveal the cliff attenuation on the oxygen evolution reaction (OER) performance of these pyrochlores. In this work, we monitor the structure changes and electrochemical behavior of Y2Ru2O7−δ over the OER process, and it is found that the reason of decisive OER inactivation is derived from an insulator transition occurred within Y2Ru2O7−δ due to its inner "perfecting" lattice induced by continuous atom rearrangement. Therefore, a stabilization strategy of the Ir‐substituted Y2Ru2O7−δ is proposed to alleviate this undesirable behavior. The double‐exchange interaction between Ru and Ir in [RuO6] and [IrO6] octahedra leads the charge redistribution with simultaneous spin configuration adjustment. The electronic state in newly formed octahedrons centered with Ru 4d3 (with the state of eg′↑↑a1g↑eg0) and Ir 5d6 (eg′↑↓↑↓a1g↑↓eg0) relieves the uneven electron distributions in [RuO6] orbital. The attenuated Jahn–Teller effect alleviates atom rearrangement, represented as the mitigation of insulator transition, surface reconstruction, and metal dissolution. As results, the Ir‐substituted Y2Ru2O7−δ presents the greatly improved OER stability and PEM durability. This study unveils the OER degradation mechanism and stabilization strategy for material design of Ru‐based OER catalysts for electrochemical applications. [ABSTRACT FROM AUTHOR]

Advancing catalyst design is pivotal for the enhancement of photocatalytic processes in renewable energy conversion. The incorporation of structural chirality into conventional inorganic solar hydrogen nanocatalysts promises a significant transformation in catalysis, a feature absent in this field. Here we unveil the unexplored potential of geometric chirality by creating a chiral composite that integrates geometric chiral Au nanoparticles (NPs) with two‐dimensional C3N4 nanosheets, significantly boosting photocatalytic H2 evolution beyond the achiral counterparts. The superior performance is driven by the geometric chirality of Au NPs, which facilitates efficient charge carrier separation through the favorable C3N4‐chiral Au NP interface and chiral induced spin polarization, and exploits high‐activity facets within the concave surfaces of chiral Au NPs. The resulting synergistic effect leads to a remarkable increase in photocatalytic H2 evolution, with an apparent quantum yield of 44.64 % at 400 nm. Furthermore, we explore the selective polarized photo‐induced carrier separation behavior, revealing a distinct chiral‐dependent photocatalytic HER performance. Our work advances the design and utilization of chiral inorganic nanostructures for superior performance in energy conversion processes. [ABSTRACT FROM AUTHOR]

Combining theory and computation, we explore the Goos–Hänchen (GH) effect for electrons in a single-layered semiconductor microstructure (SLSM) modulated by Dresselhaus spin–orbit coupling (SOC). GH displacement depends on electron spins thanks to Dresselhaus SOC, therefore electron spins can be separated from the space domain and spin-polarized electrons in semiconductors can be realized. Both the magnitude and sign of the spin polarization ratio change with the electron energy, in-plane wave vector, strain engineering and semiconductor layer thickness. The spin polarization ratio approaches a maximum at resonance; however, no electron-spin polarization occurs in the SLSM for a zero in-plane wave vector. More importantly, the spin polarization ratio can be manipulated by strain engineering or semiconductor layer thickness, giving rise to a controllable spatial electron-spin splitter in the field of semiconductor spintronics. [ABSTRACT FROM AUTHOR]

We investigate the spin- and valley-dependent transport properties of electrons in silicene modulated by metallic gates, which can produce a potential barrier to affect the electron transport. The numerical results show that in such a silicene nanostructure the large spin polarization and valley polarization can be obtained, and they are strongly dependent on the height and width of the potential barrier. Therefore, the required degree of spin polarization and valley polarization can be realized through changing the height and/or width of the potential barrier. This valuable discovery well reveals the spin- and valley-dependent electron transport mechanism in such a silicene and is helpful for designing new kinds of spintronic and valleytronic devices modulated by metallic gates. [ABSTRACT FROM AUTHOR]

Half-metallic ferromagnetic Heusler alloys having high spin polarization are promising candidates to realize large magnetoresistance (MR) ratio and high spin-transfer torque (STT) efficiency in next-generation spintronic devices. Since the Heusler alloy properties are sensitive to composition, optimizing the composition is crucial for enhancing device performance. Here, we report the fabrication of high-performance current-perpendicular-to-plane giant magnetoresistance (CPP-GMR) devices using Co2MnxFe1−xGe (0 ≤ x ≤ 1) Heusler alloy, employing a high-throughput and detailed composition optimization method. The method combined composition-gradient films and local measurements to enable the composition variation from Co2FeGe to Co2MnGe to be efficiently studied on a single library sample with a small composition interval. The CPP-GMR devices fabricated from stacks annealed at 250 °C showed a clear composition dependence of MR with the maximum of MR ratio ∼38% in the Mn-rich region of x = 0.85. By increasing the annealing temperature to 350 °C, the MR ratio increased to ∼45% along with high STT efficiency ∼0.6 in the broad composition range of 0.2 ≤ x ≤ 0.7. The optimal composition for the highest MR changed with annealing temperature because of the stability of the GMR stack being higher in the lower x range. The record high MR for the all-metal CPP-GMR devices, at low annealing temperature of 250 °C was achieved by the detailed composition optimization. These results present the high potential of Co2MnxFe1−xGe and provide a comprehensive guidance on the composition optimization for achieving large MR ratio and high STT efficiency in the CPP-GMR devices. [ABSTRACT FROM AUTHOR]

In this study, deterministic current‐induced spin‐orbit torque (SOT) magnetization switching is achieved, particularly in systems with perpendicular magnetic anisotropy (PMA), without the need for a collinear in‐plane field, a traditionally challenging requirement. In a Ta/CoFeB/MgO/NiO/Ta structure, spin reflection at the MgO/NiO interface generates a spin current with an out‐of‐plane spin polarization component σz. Notably, the sample featuring 0.8 nm MgO and 2 nm NiO demonstrates an impressive optimal switching ratio approaching 100% without any in‐plane field. A systematic investigation of the effects of the MgO and NiO thickness demonstrates that the formation of noncollinear spin structures and canted magnetization in the ultrathin NiO interlayer plays a pivotal role to the field‐free SOT switching. The integration of NiO as an antiferromagnetic insulator effectively mitigates current shunting effects and enhances the thermal stability of the device. This advancement in the CoFeB/MgO system holds promise for significant applications in spintronics, marking a crucial step toward realizing innovative technologies. [ABSTRACT FROM AUTHOR]

Single Fe sites have been explored as promising catalysts for the CO2 reduction reaction to value‐added CO. Herein, we introduce a novel molten salt synthesis strategy for developing axial nitrogen‐coordinated Fe‐N5 sites on ultrathin defect‐rich carbon nanosheets, aiming to modulate the reaction pathway precisely. This distinctive architecture weakens the spin polarization at the Fe sites, promoting a dynamic equilibrium of activated intermediates and facilitating the balance between *COOH formation and *CO desorption at the active Fe site. Notably, the synthesized FeN5, supported on defect‐rich in nitrogen‐doped carbon (FeN5@DNC), exhibits superior performance in CO2RR, achieving a Faraday efficiency of 99 % for CO production (−0.4 V vs. RHE) in an H‐cell, and maintaining a Faraday efficiency of 98 % at a current density of 270 mA cm−2 (−1.0 V vs. RHE) in the flow cell. Furthermore, the FeN5@DNC catalyst is assembled as a reversible Zn−CO2 battery with a cycle durability of 24 hours. In situ IR spectroscopy and density functional theory (DFT) calculations reveal that the axial N coordination traction induces a transformation in the crystal field and local symmetry, therefore weakening the spin polarization of the central Fe atom and lowering the energy barrier for *CO desorption. [ABSTRACT FROM AUTHOR]

Centrosymmetric materials with site inversion asymmetries possess hidden spin polarization, which remains challenging to be converted into spin currents because the global inversion symmetry is still conserved. This study demonstrates the spin-polarized circular photocurrents in centrosymmetric transition metal dichalcogenide semiconductors at normal incidence without applying electric bias. The global inversion symmetry is broken by using a spatially-varying circularly polarized light beam, which could generate spin gradient owing to the hidden spin polarization. The dependence of the circular photocurrents on electrode configuration, illumination position, and beam spot size indicates an emergence of circulating electric current under spatially inhomogeneous light, which is associated with the deflection of spin-polarized current through the inverse spin Hall effect. The circular photocurrents is subsequently utilized to probe the spin polarization and the inverse spin Hall effect under different excitation wavelengths and temperatures. The results of this study demonstrate the feasibility of using centrosymmetric materials with hidden spin polarization and non-vanishing Berry curvature for spintronic device applications. The authors report the generation of circular photocurrents from multilayer 2H-phase transition metal dichalcogenides, including MoTe2, MoS2, and WSe2, which is attributed to the manifestation of hidden spin polarization and inverse spin Hall effect. [ABSTRACT FROM AUTHOR]

By means of the first-principles method, the bias effect on the magnetism of polyacene (n-acene) connected to gold electrodes is investigated. A magnetic to nonmagnetic transition for the polyacene (n > 6) is observed when the bias exceeds a critical value. The mechanism is explored as the bias-induced variation of electronic localization, which leads to the exchange of dominant mechanism for molecular magnetism from Columbic interaction between electrons to electron hopping rate. A significant enhancement of the differential conductance and suppression of current spin polarization for the molecular device are also obtained accompanied by the transition of molecular magnetism. This work proposes a feasible way to manipulate the magnetism of polyacene via electric method and reveals the relation between molecular magnetism and its conductance. [ABSTRACT FROM AUTHOR]

In this work, CeO 2 nanocrystals with a mixture of distinct morphologies were obtained using different solvents (acetone or ethanol). The (micro)structural, sensing mechanism, and magnetic properties, as well as first-principle calculations were evaluated. XPS reveals that the sample synthesized in acetone exhibited a diminished Ce4+ content (and heightened Ce3+ concentration) compared to the sample synthesized in ethanol. In the case of the syntheses at acetone, sphere-like nanoparticles and nanorods present a predominance of surfaces (111) and (220), while the syntheses with ethanol led to a predominance of surfaces (200) for the sphere-like nanoparticles. Theoretical simulations reveal the spin polarization of f electrons in Ce ions neighboring oxygen vacancies suggests that oxygen vacancies situated at the surface may engender a greater number of magnetic moments compared to those induced by an oxygen vacancy within the bulk. At room temperature, the M S of CeO 2 nanocrystals crystallized in acetone (66.20 emu-g) surpasses that of the CeO 2 nanocrystals obtained in ethanol (24.07 emu-g), which can be attributed to the differing morphologies of the samples. Our findings illustrate that, in addition to the solvent type, the size and morphology of the particles also play a significant role in influencing the sensing mechanism and magnetic properties. Films based on CeO 2 nanocrystals synthesized via MAS using acetone and ethanol revealed a fast response time of 9.6 s and 12 s, with a recovery time of 45.6 s and 87.6 s towards CO gas, respectively, these phenomena are attributed to the presence of oxygen vacancies, which facilitate the adsorption of CO. Our findings are key for facet engineering and may provide new strategies for producing CeO 2 based-materials to be applied in morphology-dependent technologies, such as carbon monoxide (CO) gas sensors. [ABSTRACT FROM AUTHOR]

In this study, we investigate the effect of temperature on the performance of a read sensor by utilizing an atomistic model coupled with a spin transport model. Specifically, we study the temperature dependence of spin transport behavior and MR outputs in a Co 2 FeAl 0.5 Si 0.5 (CFAS)(5nm)/Cu(5nm)/CFAS(5nm) trilayer with diffusive interfaces. Initially, the two-channel model of spin-dependent resistivity is used to calculate the temperature dependence of spin transport parameters which serves as essential input for the spin accumulation model. Our findings demonstrate that as the temperature increases, the spin transport parameters and magnetic properties decrease due to the influence of thermal fluctuation. At a critical temperature, where the ferromagnet transitions to a paramagnetic state, we observe zero spin polarization. Furthermore, at elevated temperatures, the spin accumulation deviates from the equilibrium value, leading to a reduction in the magnitude of spin current and spin transport parameters due to thermal effects. As a consequence, the MR ratio decreases from 65% to 20% with increasing temperature from 0 to 400 K. Our results are consistent with previous experimental measurements. This study allows to deeply understand the physical mechanism in the reader stack which can significantly benefit reader design. [ABSTRACT FROM AUTHOR]

The use of Moore's law appears to be coming to an end due to technological and physical constraints, as complementary metal-oxide semiconductor (CMOS) transistors become smaller and closer to the atomic scale. Therefore, various emerging technologies are being researched as potential successors to traditional CMOS transistors, and one of the most exciting candidates is the magnetoelectric spin-orbit (MESO) device. The MESO device comprises two portions (input and output) and it cascades charge/voltage as input and output signals. In the MESO device's output portion, ferromagnetic (FM) and high-spin-orbit-coupling layers are employed to provide spin-polarized current and charge/voltage output. In this paper, we offer a description and analysis of the operating mechanism of the MESO device's output portion using a spin flow approach and propose a double-FM-layer structure. In the double-FM-layer structure, we implement two FM layers with antiparallel magnetization directions, instead of using a single-FM-layer structure to increase the output charge/voltage. The proposed structure is verified through the Verilog-A compact model. [ABSTRACT FROM AUTHOR]

Density functional theory with pesudo potential approximation is used to study XBaB (X = Li , Na, K) half-Heusler compounds structural, magnetic and electrical property using Quantum espresso code and thermoelectric properties were studied using BoltzTrap code. Total energy calculations were carried out in the α , β and γ phases of XBaB compounds in C 1 b type structure. The compounds were stable in α -phase and hence further calculations were focused only on α phase. From the spin polarization calculations, magnetic state was stable than nonmagnetic state and exhibits ferromagnetism at the equilibrium lattice constant with an integer magnetic moment of 2  μ B . From the band structure calculations and through density of states, all the three compounds exhibit half-metallicity with 100% spin polarization by showing semi-conductivity for majority spin and metallicity for minority spin. In addition, thermoelectric properties were investigated for all three compounds. LiBaB is found to have high Seebeck coefficient of 2462 μ VK − 1 and ZT value of 1, compared to other compounds. These materials were found to have high ZT value and hence they can be used for thermoelectric applications. [ABSTRACT FROM AUTHOR]

Novel optically active π-conjugated polymers having a chiral bifacial indacenodithiophene backbone were synthesized by Suzuki–Miyaura cross coupling polymerization with benzothiadiazole comonomer. The obtained C2-chiral polymers form amorphous thin films on HOPG and exhibit good chirality-induced spin selectivity with spin polarization of nearly 70%. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) was used to study the structural, electronic, magnetic, and optical properties of the rare-earth-based ternary chalcogenide GdCuX2 (X = S, Se, and Te). DFT calculations were performed using the Tran-Blaha modified Becke-Johnson (TB-mBJ) generalized gradient approximation (GGA), generalized gradient approximation with Hubbard U (GGA + U), and spin orbit coupling (GGA + U + SOC) potentials. In structural properties, we computed the ground state energy, with equilibrium volume, and lattice parameters for GdCuS2, GdCuSe2, and GdCuTe2 compounds. The structural properties show that the GdCuS2, GdCuSe2 and GdCuTe2 compounds have stable structures at the Wycoff position. The electronic properties were calculated in terms of the density of states (DOS) and electronic band diagram. Electronic properties confirm the semiconductor nature of GdCuS2, GdCuSe2, and GdCuTe2 compounds using TB-mBJ, GGA, and GGA + U potentials. However, the GdCuTe2 compound displays a metallic nature when using the GGA + U + SOC potential. Magnetic properties in terms of spin polarization magnetic moments of GdCuS2, GdCuSe2 and GdCuTe2 compounds. With magnetic optimisation, we made a graph of the energy vs. volume curve to show that ferromagnetic [FM] is more stable than antiferromagnetic [AFM] and nonmagnetic [NM]. The GdCuS2, GdCuSe2 and GdCuTe2 compounds show a good ferromagnetic nature. The optical properties of the compounds in terms of dielectric functions, refractive indices, and absorption coefficients. In the visible and infrared ranges, the optical properties reveal an upstate semiconductor nature and a downstate metallic nature. In the higher energy range, the maximum absorption is observed in the optical properties. [ABSTRACT FROM AUTHOR]

In this study, the electronic and magnetic properties of hydrogen-passivated armchair and zigzag GaN nanoribbons are investigated using density-functional theory. We explore that doped TM atom leads to additional levels in the band gap and thus plays an essential role in spin polarization and changes their properties. Depending on its location in the nanoribbon, the character of spin-dependent electronic property of a doped GaN-NR was analyzed. Our calculations show that, regardless of the position of Mn atoms, GaNNTs are stable in ferromagnetic phase. [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]

Sluggish ion diffusion of large sodium ions is one of the main drawbacks challenging the development of metal selenides‐based anode materials for sodium‐ion batteries (SIBs). A spin‐state regulating strategy is first proposed in this work to lift the p‐band center (ɛp) of Se for a fast Na+ transfer kinetic in (Co,Cu)Se2. By utilizing the electron transfer from Cu to Co, the π‐symmetry t2g of Co is fully occupied to decrease the spin polarization. The resultant electron repulsion between Co and Se weakens Co–Se bond to lift the ɛp of Se. The enhanced sodium adsorption energy effectively accelerates the ion transfer at the active material–electrolyte interface. As a result, the (Co,Cu)Se2/NC electrode exhibits an superior sodium storage performance with a capacity of 445 mAh g−1 at 0.2 A g−1, 312 mAh g−1 at 50 A g−1, and 363 mAh g−1 after 10 000 cycles at 10.0 A g−1. The insight into the working mechanism of regulating spin‐state of metals to lift the p‐band center of Se can provide guidelines for the development of both metal selenides‐based anode material and high‐performance SIBs. [ABSTRACT FROM AUTHOR]

In this work, silicon microcrystals doped with a boron impurity to concentrations corresponding to the metal-dielectric transition in silicon of 5.5·1018 cm−3 and a nickel impurity in the temperature range of 4.2 ÷ 70 K under alternating current in the frequency range of 0.010 ÷ 250 kHz were studied. The features of the frequency response of silicon microcrystals are determined. On the basis of Nyquist diagrams, an equivalent conductivity scheme at low temperatures is proposed. The frequency response of the samples was evaluated and the mechanisms of charge carrier flow were proposed depending on the observation conditions. Conduction mechanisms from quantum mechanical tunneling (QMT) to superlinear power law (SLPL), which can be implemented in crystals, are considered. [ABSTRACT FROM AUTHOR]

A metal complex (R-TAP-Pd(II)) constructed by chiral molecule R-TAP coordinated Pd(II) was used to modify g-C 3 N 4 to promote the separation efficiency of photogenerated carriers. Meanwhile, the R-TAP-Pd(II) acts as an activation site for proton reduction reaction, which enhances the photocatalytic H 2 evolution. [Display omitted] The photocatalytic H 2 production activity of polymer carbon nitride (g-C 3 N 4) is limited by the rapid recombination of photoelectron-hole pairs and slow surface reduction dynamic process. Here, a supramolecular complex (named R-TAP-Pd(II)) was fabricated via self-assembly of (R)-N-(1-phenylethyl)-4-(4-(pyridin-2-yl)-1H-1,2,3-triazol-1-yl)benzamide (R-TAP) with Pd(II) and used to modify g-C 3 N 4. In the R-TAP-Pd(II)@g-C 3 N 4 composite photocatalyst, the spin polarization of R-TAP-Pd(II) can promote charge transfer and inhibit photogenerated carrier recombination, as confirmed by spectral tests and photoelectrochemical performance tests. Electrochemical tests and in situ X-ray photoelectron spectroscopy (XPS) tests proved that the Pd(II) ion in the R-TAP-Pd(II) molecule can serve as active sites to accelerate H 2 production. The R-TAP-Pd(II)@g-C 3 N 4 presented a photocatalytic H 2 generation rate of 1085 μmol g−1 h−1 when exposed to visible light, which was a about 278-fold increase compared with g-C 3 N 4. This work finds a new approach to boost the photocatalytic efficiency of g-C 3 N 4 via supramolecular self-assembly. [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]

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]

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]