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The composition-dependent spin exchange interaction in a perovskite-structured Pb(Fe0.5−xNix)Nb1/2O3 system has been studied to understand its multiferroicity at room-temperature. Special emphasis was paid to the magnetic behavior in terms of magnetic moment, interatomic distance, and atomic ordering because they play a key role in the modulation of magnetic multiferroic behavior. We observed that 10 mol. % Ni incorporation led to multiferroic behavior with considerable ferrimagnetic properties (saturation magnetization of 0.6 emu/g and a coercive field of 20 Oe) coupled with the inherent properties of displacive ferroelectricity (spontaneous polarization of 20 μC/cm2). A subsequent increase in the Ni substitution degree degraded the ferroelectricity due to a phase transition from a non-centrosymmetric rhombohedral to a centrosymmetric cubic system. We have shown that magnetic spins with a pronounced magnetic moment along the [001] direction are ferrimagnetically arranged when the interatomic distance between the magnetic transition metals at the octahedral site is less than 4 Å, resulting in significant magnetic properties The objective of this study is to provide a general methodology for modulating magnetic orders in ferroelectric perovskite oxides. [ABSTRACT FROM AUTHOR]

The composition-dependent spin exchange interaction in a perovskite-structured Pb(Fe0.5−xNix)Nb1/2O3 system has been studied to understand its multiferroicity at room-temperature. Special emphasis was paid to the magnetic behavior in terms of magnetic moment, interatomic distance, and atomic ordering because they play a key role in the modulation of magnetic multiferroic behavior. We observed that 10 mol. % Ni incorporation led to multiferroic behavior with considerable ferrimagnetic properties (saturation magnetization of 0.6 emu/g and a coercive field of 20 Oe) coupled with the inherent properties of displacive ferroelectricity (spontaneous polarization of 20 μC/cm2). A subsequent increase in the Ni substitution degree degraded the ferroelectricity due to a phase transition from a non-centrosymmetric rhombohedral to a centrosymmetric cubic system. We have shown that magnetic spins with a pronounced magnetic moment along the [001] direction are ferrimagnetically arranged when the interatomic distance between the magnetic transition metals at the octahedral site is less than 4 Å, resulting in significant magnetic properties The objective of this study is to provide a general methodology for modulating magnetic orders in ferroelectric perovskite oxides. [ABSTRACT FROM AUTHOR]

Density functional approximations to the exchange–correlation energy can often identify strongly correlated systems and estimate their energetics through energy-minimizing symmetry-breaking. In particular, the binding energy curve of the strongly correlated chromium dimer is described qualitatively by the local spin density approximation (LSDA) and almost quantitatively by the Perdew–Burke–Ernzerhof generalized gradient approximation (PBE-GGA), where the symmetry breaking is antiferromagnetic for both. Here, we show that a full Perdew–Zunger self-interaction-correction (SIC) to LSDA seems to go too far by creating an unphysical symmetry-broken state, with effectively zero magnetic moment but non-zero spin density on each atom, which lies ∼4 eV below the antiferromagnetic solution. A similar symmetry-breaking, observed in the atom, better corresponds to the 3d↑↑4s↑3d↓↓4s↓ configuration than to the standard 3d↑↑↑↑↑4s↑. For this new solution, the total energy of the dimer at its observed bond length is higher than that of the separated atoms. These results can be regarded as qualitative evidence that the SIC needs to be scaled down in many-electron regions. [ABSTRACT FROM AUTHOR]

We conducted spin Hall magnetoresistance (SMR) measurements to investigate the Ru-doping effect on the Morin transition of α-Fe2O3(0001) films, which is the transition from the low-temperature antiferromagnetic state with c-axis magnetic moments to the high-temperature weak ferromagnetic state with c-plane magnetic moments, under a thickness of 6–100 nm. We clarified that the Morin temperature of the 2.6 at. % Ru-doped α-Fe2O3 film was greater than 400 K when the thickness was 100 nm and decreased with a decrease in thickness. Our results demonstrated that SMR measurements are a valid verification method for the Morin transition of very thin α-Fe2O3 films down to several nm. [ABSTRACT FROM AUTHOR]

VO2 is renowned for its electric transition from an insulating monoclinic (M1) phase, characterized by V–V dimerized structures, to a metallic rutile (R) phase above 340 K. This transition is accompanied by a magnetic change: the M1 phase exhibits a non-magnetic spin-singlet state, while the R phase exhibits a state with local magnetic moments. Simultaneous simulation of the structural, electric, and magnetic properties of this compound is of fundamental importance, but the M1 phase alone has posed a significant challenge to the density functional theory (DFT). In this study, we show none of the commonly used DFT functionals, including those combined with on-site Hubbard U to treat 3d electrons better, can accurately predict the V–V dimer length. The spin-restricted method tends to overestimate the strength of the V–V bonds, resulting in a small V–V bond length. Conversely, the spin-symmetry-breaking method exhibits the opposite trends. Each of these two bond-calculation methods underscores one of the two contentious mechanisms, i.e., Peierls lattice distortion or Mott localization due to electron–electron repulsion, involved in the metal–insulator transition in VO2. To elucidate the challenges encountered in DFT, we also employ an effective Hamiltonian that integrates one-dimensional magnetic sites, thereby revealing the inherent difficulties linked with the DFT computations. [ABSTRACT FROM AUTHOR]

The effect of the YBCO superconducting (SC) state on the magnetic properties of as-grown YBCO/Co/IrMn heterostructures has been systematically studied using magnetometry and ferromagnetic resonance. The obtained data showed that the superconductivity of the YBCO substrate strongly affects the ferromagnetic properties of the deposited Co layer deeper (up to 50 nm) than the coherence length of the YBCO (≃ 4 nm) by an exchange interaction between the Co magnetic moments and the superconducting pairs at the YBCO/Co interface. The interfacial exchange interaction, switched on while the YBCO enters the SC state, pins Co spins and yields an enhancement of the Co magnetic properties. [ABSTRACT FROM AUTHOR]

VO2 is renowned for its electric transition from an insulating monoclinic (M1) phase, characterized by V–V dimerized structures, to a metallic rutile (R) phase above 340 K. This transition is accompanied by a magnetic change: the M1 phase exhibits a non-magnetic spin-singlet state, while the R phase exhibits a state with local magnetic moments. Simultaneous simulation of the structural, electric, and magnetic properties of this compound is of fundamental importance, but the M1 phase alone has posed a significant challenge to the density functional theory (DFT). In this study, we show none of the commonly used DFT functionals, including those combined with on-site Hubbard U to treat 3d electrons better, can accurately predict the V–V dimer length. The spin-restricted method tends to overestimate the strength of the V–V bonds, resulting in a small V–V bond length. Conversely, the spin-symmetry-breaking method exhibits the opposite trends. Each of these two bond-calculation methods underscores one of the two contentious mechanisms, i.e., Peierls lattice distortion or Mott localization due to electron–electron repulsion, involved in the metal–insulator transition in VO2. To elucidate the challenges encountered in DFT, we also employ an effective Hamiltonian that integrates one-dimensional magnetic sites, thereby revealing the inherent difficulties linked with the DFT computations. [ABSTRACT FROM AUTHOR]

In recent few years, the two-dimensional (2D) magnets have emerged as one of the most important frontiers in materials physics and attracted much attention. As one of the earliest experimentally discovered 2D magnets, CrI3 shows a wealth of properties and has been extensively studied. In particular, an intriguing characteristic of the CrI3 monolayer is its octahedrally coordinated hollow within the unit-cell, which enables the implantation of a magnetic atom, thereby resulting in an artificial 2D superlattice with fertile physics to explore. In this work, using first-principles calculations, we investigate the Co-implanted CrI3 monolayer, denoted as Co-(CrI3)2, and demonstrate the vital roles of the exchange channels of eg electrons in enhancing magnetism. It is shown that the Co-(CrI3)2 monolayer has a half-metallic ferrimagnetic (FiM) ground-state with a net in-plane magnetic moment of 5.0μB/f.u. and a relatively high Curie point (TC) of ∼195 K, noting that TC of pristine CrI3 is only 45–61 K. The FiM ordering is established by the strong anti-ferromagnetic coupling in the t2g-eg exchange channels of the nearest-neighbor (NN) Cr–Co pair and the sizeable ferromagnetic coupling of the third NN Cr–Cr pair mediated by the itinerant eg electrons. In addition, an in-plane biaxial tensile strain of ∼2% may further enhance TC up to ∼210 K. This work offers unique insights into the magnetism enhancement of the CrI3 monolayer by atom-implantation, paving the way for the development of 2D magnets. [ABSTRACT FROM AUTHOR]

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

Based on density functional theory, structural, electronic, magneto-optic, and thermoelectric properties of RbCaN2 and RbCaO2, Heuslerene compounds have been calculated. These compounds have the ground state points with total magnetic moment of 1.0 μ B , which represents their ferromagnetic behavior. The RbCaN2 Heuslerene has the half-metallic nature and RbCaO2 case is a magnetic semiconductor. The Kerr angle of the RbCaN2 Heuslerene has two relatively peaks at the energies of 5.5 eV to 7.0 eV, but for the RbCaO2 compound, this diagram is wider in a larger energy range. Faraday angle peaks occurred at 6.2 eV and 6.8 eV for RbCaN2 and RbCaO2 compounds, which indicates the polarization of the light irradiated to them at these energies. It was observed that both compounds show high thermoelectric quality at temperatures higher than the room-temperature, and both compounds are suitable for power generator applications. [ABSTRACT FROM AUTHOR]

The Mn X Tm 1‒X Se (0 ≤ Х ≤ 0.2) solid solutions have been first synthesized and their structural, magnetic, and transport properties have been studied in the temperature range of 80–1000 K and magnetic fields of up to 12 kOe. The surface morphology of the samples has been examined and the chemical analysis has been carried out. It is shown that the valence change with the increasing substitution concentration is accompanied by a change in the lattice parameter and a decrease in the magnetic moment of the samples. The Kondo temperatures caused by the manganese and thulium subsystem have been found in the low- and room-temperature regions. The temperature of localization of small-radius polarons has been determined. A drastic decrease in the relaxation time in the range of the manganese ion percolation through the lattice in the Mn X Tm 1‒X Se system has been established. The change of the current carrier type upon variation in the temperature and substitution concentration was determined from the Seebeck coefficient. A high-temperature extremum of thermopower was revealed, which is explained within the framework of the Anderson model. [ABSTRACT FROM AUTHOR]

Magnetic topological insulators exhibit unique electronic states due to the interplay between the electronic topology and the spin structure. The antiferromagnetic metal EuIn2As2 is a prominent candidate material in which exotic topological phases, including an axion insulating state, are theoretically predicted depending on the magnetic structure of the Eu2+ moments. Here, we report experimental results of the nuclear magnetic resonance (NMR) measurements of all the nuclei in EuIn2As2 to investigate the coupling between the magnetic moments in the Eu ions and the conduction electrons in In2As2 layers and the magnetic structure. The 75As and 115In NMR spectra observed at zero external magnetic fields reveal the appearance of internal fields of 4.9 and 3.6 T, respectively, at the lowest temperature, suggesting a strong coupling between the conduction electrons in the In2As2 layer and the ordered magnetic moments in the Eu ions. The 75As NMR spectra under in-plane external magnetic fields show broad distributions of the internal fields produced by an incommensurate fan-like spin structure which turns into a forced ferromagnetic state above 0.7 T. We propose a spin reorientation process that an incommensurate helical state at zero external magnetic field quickly changes into a fan state by applying a slight magnetic field. [ABSTRACT FROM AUTHOR]

Nitride perovskites ABN3 are an emerging and highly underexplored class of materials that are of interest due to their intriguing calculated ferroelectric, optoelectronic, and other functional properties. Incorporating novel A-site cations is one strategy to tune and expand such properties; for example, Gd3+ is compelling due to its large magnetic moment, potentially leading to multiferroic behavior. However, the theoretically predicted ground state of GdWN3 was a non-perovskite monoclinic structure. Here, we experimentally show that GdWN3−y crystallizes in a perovskite structure. High-throughput combinatorial sputtering with activated nitrogen is employed to synthesize thin films of Gd2−xWxN3−yOy with oxygen content y < 0.05. Ex situ annealing crystallizes a polycrystalline perovskite phase in a narrow composition window near x = 1. LeBail fits of synchrotron grazing incidence wide angle x-ray scattering data are consistent with a perovskite ground-state structure. Refined density functional theory calculations that included antiferromagnetic configurations confirm that the ground-state structure of GdWN3 is a distorted Pnma perovskite with antiferromagnetic ordering, in contrast to prior predictions. Initial property measurements find that GdWN3−y is paramagnetic down to T = 2 K with antiferromagnetic correlations and that the absorption onset depends on cation stoichiometry. This work provides an important path toward both the rapid expansion of the emerging family of nitride perovskites and understanding their potential multiferroic properties. [ABSTRACT FROM AUTHOR]

This study focuses on baryons that consists of one heavy quark and two light quarks. This paper explores the mass spectra of radial and excited states for all singly heavy baryons, employing the Hypercentral Constituent Quark Model (hCQM). In this model, we incorporated higher-order corrections, including second-order corrections in mass, specifically considering spin-dependent terms. This methodology enables a more accurate observation of the correct spin splitting order. We have determined important properties, including magnetic moment, transition magnetic moment, radiative decay width and strong decay width. [ABSTRACT FROM AUTHOR]

With the interplay between magnetism and topological bands, magnetic kagome semimetals provide promising platforms for exploring exotic correlated electronic states and quantum phenomena such as anomalous Hall effect, quantum spin liquid, and unconventional magnetoresistance, as well as driving advances in electronic and spintronic applications. Here, a field‐induced butterfly‐like anomalous anisotropic magnetoresistance (AMR) effect in an intriguing kagome semimetal Co3In2S2 is reported. The kagome‐lattice Co3In2S2 single crystals are synthesized via a polycrystal‐source chemical vapor transport approach, possessing a high carrier mobility reaching 104 cm2V−1s−1. The Co3In2S2 single crystal exhibits a canted antiferromagnetic state below 5 K, but intriguingly, it is easily transformed into a ferromagnetic state under a small external magnetic field. Furthermore, the planar Hall effect (PHE) is detected, stemming from the complex contribution of field‐induced ferromagnetism and orbital magnetoresistance. Remarkably, as the magnetic field increases, the low‐temperature magnetoresistance behavior of the Co3In2S2 reveals a butterfly‐like AMR effect with a maximum value of 850%, exhibiting a superposition of the two‐, four‐, and six‐fold AMR terms. Band structure calculations suggest that such a field‐induced butterfly‐like AMR effect may originate from the modulations of the electronic structure near the Fermi level by the magnetic moment. The findings offer a valuable platform for understanding the anomalous AMR effect and for the development of advanced spintronic devices. [ABSTRACT FROM AUTHOR]

K20 microwave dielectric ceramics SrLnAlO 4 (Ln = Eu, Gd, and Ho) were prepared at 1440–1520 °C. SrEuAlO 4 and SrGdAlO 4 crystallized into tetragonal K 2 NiF 4 -type structures. While SrHoAlO 4 was a mixture (SrHo 2 Al 2 O 7 , Ho 2 O 3 , and Sr 3 HoAl 2 O 7.5) due to the too-small radius of Ho3+ to bond in [HoO 9 ] dodecahedron. SrEuAlO 4 and SrGdAlO 4 exhibited near-zero τ f values of +1.7 and +4.3 ppm/°C and low ε r (19.37 and 19.14) along with contrasting Q × f values (70,030 and 5560 GHz). Compared with the modified molecular polarizability (α Corr) based on the bond valence deviation, the α obs values of SrEuAlO 4 and SrGdAlO 4 are much higher, indicating that their dielectric polarizabilities were underestimated, and this phenomenon was mainly influenced by rattling cations, which also causes their τ f with near-zero values. Due to the magnetic subsystem adversely affecting microwave dielectric losses, the worsened Q × f value of SrGdAlO 4 compared to that of SrEuAlO 4 is due to the high magnetic moment of Gd3+ (7.94 μ B). [ABSTRACT FROM AUTHOR]

Investigating novel compounds has become necessary due to the need for sophisticated materials in optoelectronic devices and spintronics. Because of their unique properties, magnesium-based spinels MgSm2X4 (X = S and Se) are very promising for these applications. We used the spin-polarized PBEsol for structural properties and the PBEsol functional for mechanical behavior, both using the WIEN2k code. Both compounds' stability in the magnetic and non-magnetic phases was validated by the Birch-Murnaghan equation of state, and their stability in the cubic phase was verified by the Born stability criterion. Their ductile character was shown by the computation of Pugh's ratio and Poisson ratio. Both MgSm2S4 and MgSm2Se4 display metallic behavior in the spin-up channel and semiconducting behavior in the spin-down channel, indicating a half-metallic nature, according to TB-mBJ potential calculations. With total magnetic moments of 20 μB, both materials showed ferromagnetic properties. Samarium ions contributed 5.27 μB for MgSm2S4 and 5.34 μB for MgSm2Se4. Furthermore, we computed optical parameters in the energy range of 0 to 15 eV, such as absorption, extinction coefficient, reflectivity, dielectric function, and refractive index. Our results demonstrate the potential of MgSm2X4 spinels for future technological developments by revealing their prospective optoelectronic and spintronic applications. [ABSTRACT FROM AUTHOR]

Ensembles of suspended spinning particles in liquids form a distinct category of active matter systems known as chiral fluids. Recent experimental instances of dense chiral fluids have comprised of spinning colloidal magnets powered by an external rotating magnetic field. These particles interact through both magnetic and hydrodynamic forces, organizing collectively into circulating clusters characterized by unidirectional edge flows. Here, we externally drive the collective behavior of spinning colloids by leveraging diffusiophoretic interactions among the geometrically anisotropic particles. We show that these nanoscale interfacial flows lead to the formation of bound states between spinning colloids that are stabilized through near-field hydrodynamic and chemical interactions. At a collective level, we demonstrate that added diffusiophoretic interactions cause a loss in structural cohesion of the circulating clusters and promote expansion, while preserving global cluster inter-connectivity. The expanded cluster state is characterized by the formation of a dynamic interconnected network promoted by axi-asymmetric interactions around particles with attractive dipolar interactions dominating along the direction of the magnetic moment. This process is observed to be entirely reversible, offering external control over the emergent dynamics in dense chiral fluids, paving the way for new self-organization routes in chiral fluids and broader forms of active matter. Chiral active systems are composed of spinning constituent particles that self-organize into complex structures through hydrodynamic interactions. The authors develop methods to control these self-organized structures by introducing additional chemical interactions between spinning particles. [ABSTRACT FROM AUTHOR]

In this study, we investigate the spin-polarized characteristics of barium-based oxide perovskites BaXO3 (X = Cr, Mn, Sc). Initially, we explore the structural stability of BaXO3 (X = Cr, Mn, Sc) in ferromagnetic, anti-ferromagnetic and non-magnetic phases. We found that the ferromagnetic phase is more stable than the non-magnetic phase. Next, we investigate the electronic and magnetic properties of the perovskites BaXO3 (X = Cr, Mn, Sc) using two different approximation methods, namely GGA and TB-mBJ. By analyzing both the density of states and the band structure, we identified that the barium-based oxide perovskites under investigation exhibit half-metallic character. Furthermore, we analyzed the magnetic property of BaXO3 (X = Cr, Mn, Sc). We identified that all the perovskites have integer spin magnetic moments, confirming their half-metallic nature. Finally, we studied the various thermodynamic properties of BaXO3 (X = Cr, Mn, Sc) by varying the temperature using the quasi-harmonic approximation. The results show that the specific heat capacity of the perovskites increases with increasing temperature and saturates at a certain point. We also found that the lattice parameter of the perovskites increases with increasing temperature, indicating thermal expansion. [ABSTRACT FROM AUTHOR]

Heusler compounds belong to a large family of materials and exhibit numerous physical phenomena with promising applications, particularly ferromagnetic Weyl semimetals for their use in spintronics and memory devices. Here, anomalous Hall transport is reported in the room‐temperature ferromagnets NiMnSb (half‐metal with a Curie temperature (TC) of 660 K) and PtMnSb (pseudo half‐metal with a TC of 560 K). They exhibit 4 µB/f.u. magnetic moments and non‐trivial topological states. Moreover, NiMnSb and PtMnSb are the first half‐Heusler ferromagnets to be reported as Weyl semimetals, and they exhibit anomalous Hall conductivity (AHC) due to the extended tail of the Berry curvature in these systems. The experimentally measured AHC values at 2 K are 1.8 × 102 Ω−1 cm−1 for NiMnSb and 2.2 × 103 Ω−1 cm−1 for PtMnSb. The comparatively large value between them can be explained in terms of the spin‐orbit coupling strength. The combined approach of using ab initio calculations and a simple model shows that the Weyl nodes located far from the Fermi energy act as the driving mechanism for the intrinsic AHC. This contribution of topological features at higher energies can be generalized. [ABSTRACT FROM AUTHOR]

Mn4N/(Mn,Cu)4N epitaxial bilayer structures with (Mn,Cu)4N compositions below and above the magnetization compensation composition were prepared on SrTiO3(001) substrates by molecular beam epitaxy. The thickness of the (Mn,Cu)4N layer was fixed at approximately 20 nm, while that of the Mn4N layer was changed from 7.5 to 19.6 nm. Cross-sectional elemental mapping proved that the diffusion of Cu from the (Mn,Cu)4N layer to the Mn4N layer was negligible. The magnetization curves showed that the magnetic moments of Mn4N and (Mn,Cu)4N were antiferromagnetically coupled, independent of the Mn4N film thickness, indicating a synthetic ferrimagnetic structure. The dependence of magnetic order on Mn4N film thickness was confirmed by surface-sensitive measurements using polar magneto-optical Kerr effect and x-ray magnetic circular dichroism. This is due to the change in the layer with dominant magnetization and the strength of the antiferromagnetic coupling. The temperature dependence of the anomalous Hall effect showed that the antiferromagnetic coupling was retained in the Mn4N(7.5 nm)/(Mn,Cu)4N(22.4 nm) structure over a wide temperature range of 10–350 K. [ABSTRACT FROM AUTHOR]

This study presents an unmanned aerial vehicle (UAV)-borne vector magnetometer (MAG) system and proposes a new data-processing technique for modeling the residual magnetic anomalies of three types of landmines: the metallic antitank M15, the metallic antipersonnel M16, and the minimum-metal antitank M19. The burial depth and magnetic moment of these landmines were estimated using the measured and simulated residual magnetic anomalies based on the proposed UAV-borne vector MAG model. Initial in-flight validation showed a strong correlation between the residual magnetic anomaly maps obtained from measurements and simulations. To verify the detection capability in real-world conditions, the UAV-borne MAG system was tested at the Korean Combat Training Center. Both simulations and experiments demonstrated the effectiveness of the proposed data-processing method and UAV-borne MAG model in accurately modeling the residual magnetic anomalies of landmines with metallic components. This approach will facilitate the automated detection of M15, M16, and M19 landmines with high detection rates and enable accurate classification. [ABSTRACT FROM AUTHOR]

An experimental and theoretical investigation of the magnetic properties of Ti-doped barium hexaferrite (BaM) is conducted. Polycrystalline samples of BaFe 12 − x Ti x O 19 with x ≤ 0.2 were synthesized using the solid-state reaction method. X-ray diffraction (XRD) analyses, along with Rietveld refinement, confirmed the presence of BaFe 12 O 19 as the predominant BaM phase and a minor amount of hematite in all samples. Structural analysis revealed a slight increase in lattice parameters a and c for x = 0. 2. A result mostly related to the preferential occupation of Ti 4 + ions at the 4f 2 and 12k sites, coupled with the reduction of Fe3＋ ions to Fe2＋. It was also found that the magnetic response of samples is affected by Ti 4 + substitution. Saturation magnetization slightly decreased from ∼ 45 (x = 0) to ∼ 44 emu/g (x = 0.2), the anisotropy constant from ∼ 4. 08 × 105 to ∼ 4. 06 × 105 erg/g 2 , while coercivity slightly increased from ∼ 2456 to ∼ 2468 Oe, and the anisotropy field from ∼ 18.2 to ∼ 18.6 kOe. The magnetic features of the samples were analyzed in terms of a proposed model based on the mean-field theory. Results indicated that the substitution of Ti 4 + ions resulted in a decrease in the magnetic moment of the 2b sublattice. Such behavior is influenced by its closest neighboring sites 12k and 4f 2 sublattices, which are the preferred occupancy sites for the Ti 4 + cations. [ABSTRACT FROM AUTHOR]

Electrochemical splitting of water for hydrogen generation has emerged as a potential strategy for transitioning towards renewable energy sources and mitigating the environmental impact of fossil fuel dependence. However, the efficiency of water splitting is mainly hindered by oxygen evolution reaction (OER) at the anode side, which involves kinetically sluggish four proton‐coupled electron‐transfer steps. Recent studies on OER demonstrate that a spin‐dependent mechanism governs the reaction kinetics, wherein the electronic exchange interactions in the catalytic activity of transition metals can provide a spin‐selective channel to filter out electron spins with the right orientation during the formation of O2. Maximizing efficiency and stability of such catalysts require optimization the geometric and electrical structures of transition metal systems. In addition, it is vital to understand the OER mechanism with spin considerations to be familiar with the connection between spin, charge, orbital, and lattice characteristics. This review focuses on current developments in understanding and the use of the spin‐related effect in the OER mechanism. [ABSTRACT FROM AUTHOR]

We observe concurrent precessional and partial orbital motion of highly birefringent liquid crystal (LC) particles trapped in a spherically aberrated optical trap, which is built employing a tilted refractive index stratified medium. For input circularly polarized light, the breaking of azimuthal symmetry induced by the tilt leads to an asymmetric intensity distribution in the radial direction near the trap focal plane, which—in combination with the spin–orbit conversion effects for input circularly polarized light—results in nonuniform canonical and spin momentum densities in those regions. In addition, while the canonical momentum remains always oriented toward the axial direction, the spin momentum reverses direction along spatial loops in the radial direction. As a consequence, the total momentum precesses around the canonical momentum vector along elliptical spatial loops—akin to a Larmor-like precession of magnetic moment (total momentum in our case) around a magnetic field (canonical momentum). We probe this precession experimentally using the single trapped LC particles—with the direction of precession and orbital motion determined by the helicity of the input light, with the precession frequency varying linearly with the laser power. Our experimental results are validated by numerical simulations of the system where we employ the Debye–Wolf theory for tight focusing in the presence of a tilted stratified media. [ABSTRACT FROM AUTHOR]

The exchange bias (EB) effect plays an undisputed role in the state‐of‐art spintronic devices, both rigid and flexible. However, the poor stability of EB under mechanical strain is detrimental to the construction of reliable flexible spintronic devices, which poses a great challenge for potential wearable applications. Here, it is revealed that the strain‐induced variation of EB field can be greatly suppressed by engineering flexible IrMn/[Co/Pt]3 systems featured with perpendicular magnetic anisotropy (PMA). Particularly, in the multi‐stacks with strong PMA, poorly crystallized IrMn structure, and parallel alignment of the ferromagnetic (FM) moments with the biasing magnetic field applied during deposition, an exceptional good strain stability of EB among reported flexible systems is realized, which results from the stable perpendicular FM moments, the low strain transfer efficiency, and the eliminated strain‐driven training effect. These results provide an effective approach to develop flexible spintronic devices with superior strain stability, rendering them strong contenders in the realms of sensor and storage applications. [ABSTRACT FROM AUTHOR]

The emerging technique of neutral beam microscopy offers a non-perturbative way of imaging surfaces of various materials which cannot be studied using conventional microscopes. Current neutral beam microscopes use either diffractive focusing or pin-hole scanning to achieve spatial resolution, and are characterised by a strong dependence of the imaging time on the required resolution. In this work we introduce an alternative method for achieving spatial resolution with neutral atom beams which is based on manipulating the magnetic moments of the beam particles in a gradient field, and is characterised by a much weaker dependence of the imaging time on the image resolution. The validity of the imaging approach is demonstrated experimentally by reconstructing one dimensional profiles of the beam which are in good agreement with numerical simulation calculations. Numerical simulations are used to demonstrate the dependence of the signal to noise on the scan resolution and the topography of the sample, and assess the broadening effect due to the spread of velocities of the beam particles. The route towards implementing magnetic encoding in high resolution microscopes is discussed. An alternative approach for achieving resolution in neutral beam microscopes is presented. The reciprocal space approach involves magnetically manipulating the spin of the beam atoms to encode their position and offers favourable scaling of the measurement time with the image resolution. [ABSTRACT FROM AUTHOR]

Magneto‐mechano‐electric (MME) energy harvesters (EHs) have emerged as a promising solution for powering Internet of Things (IoT) sensor networks by capturing ambient stray magnetic fields in urban circumstance. Despite significant advancements, achieving milliwatt‐level power generation from extremely weak (<1 Oe) and randomly oriented magnetic fields remains challenging. Drawing inspiration from the configuration of cross‐shaped spider legs, this study introduces an innovative X‐shaped MME‐EH featuring fourfold symmetric architecture with symmetrically distributed magnets at each end, enabling near‐isotropic in‐plane omnidirectional energy harvesting. Under extremely weak magnetic fields 0.75 and 0.3 Oe at 60 Hz, the device achieves a record‐high output power of 7.31 and 1.67 mWRMS, respectively, representing a 362% improvement in normalized power over the state‐of‐the‐art results. The theoretical model attributes these gains to the synergistic enhancement effect of the second bending mode and the dual‐mode structure, collectively improving both magnetomechanical and electromechanical coupling by augmenting the magnetic moments and suppressing the clamp loss. The device further demonstrates robust real‐world applications, efficiently powering a wireless IoT sensor system by harvesting multidirectional magnetic field energy from household appliances. This work opens new avenues for developing efficient multimodal MME‐EHs capable of harnessing omnidirectional, weak magnetic fields for widespread IoT applications. [ABSTRACT FROM AUTHOR]

The study looks into magnetically induced orientational transitions in suspensions of goethite nanorods based on a nematic liquid crystal. The study considers magnetically compensated suspension, which is a liquid-crystal analogue of an antiferromagnet. Unlike conventional magnetic particles, goethite nanorods have a remanent magnetic moment directed along the long axis of the particle and also they have negative diamagnetic anisotropy. Thus, it can be claimed that liquid-crystal composites of goethite nanorods have three mechanisms of interaction with an external magnetic field. The first two mechanisms are originally quadrupolar and are related to diamagnetic susceptibility anisotropies of liquid-crystal matrix and impurity goethite nanorods. The third mechanism is a dipolar one and is due to a remanent longitudinal magnetic moment of each dispersed particle. The magnetic-field-induced birefringence is used to show that the presence of three competing orientational mechanisms of interaction with an external magnetic field can both increase and decrease the Fréedericksz transition threshold compared to a pure liquid crystal. Diagrams of orientational phases of the suspension were constructed, and cases of various orientational mechanism predominance were analysed. Besides, a representation of the free energy of the suspension near the Fréedericksz transition in the form of the Landau expansion was obtained. This made it possible to establish that the Fréedericksz transition can occur as a phase transition of both the first and second order. [ABSTRACT FROM AUTHOR]

We study systematically magnetic moments of hiddden-bottom pentaquark states with quantum numbers J P = 1 2 ± , J P = 3 2 ± , and J P = 5 2 ± with molecular, diquark–diquark–antiquark, and diquark–triquark models. The numerical results show that magnetic moments are different within the same model according to same quantum numbers and spin-orbit couplings. The results are also different when different models are taken into account with the same angular momentum. The magnetic moments encode valuable information about inner structures. We believe that our results may be helpful for experimental studies. [ABSTRACT FROM AUTHOR]

We study neutrino spin oscillations while the particles scatter off a rotating black hole surrounded by a thick magnetized accretion disk. Neutrino spin precession is caused by the interaction of the neutrino magnetic moment with the magnetic field in the disk which has both toroidal and poloidal components. Our calculation of the observed neutrino fluxes, accounting for spin oscillations, are based on numerical simulations of the propagation of a great number of incoming test particles using High Performance Parallel Computing. The obtained results significantly improve our previous findings. We briefly discuss the applications for the observations of astrophysical neutrinos. [ABSTRACT FROM AUTHOR]

To search for proton Electric Dipole Moments (EDM) using proton storage ring with purely electrostatic elements, the concept of frozen spin method has been proposed by Brookhaven National Laboratory. This method is based on two facts: in the equation of spin precession, the magnetic field dependence is entirely eliminated, and at the "magic" energy, the spin precession frequency coincides with the precession frequency of the particle momentum. In case of deuteron, we have to use the electrical and magnetic field simultaneously, keeping the frozen spin direction along the momentum as in the pure electrostatic ring. Later, Yu. Senichev proposed the concept of quasi-frozen spin, in which the spin oscillates around the direction of the pulse within half the value of the advanced phase of rotation in magnetic arcs, each time returning back in deflectors with an electrostatic field. Due to the low value of the anomalous magnetic moment of deuteron, an effective contribution to the expected EDM effect is reduced only by a few percent compared with frozen spin method. In this work, we consider the adapted structure of the NICA and Nuclotron synchrotrons, in which the "quasi-frozen spin" option can be implemented. The advantage of the "quasi-frozen spin" concept is the possibility of using synchrotrons already existing in the world that are not focused on studying EDM, which makes this method the only one possible for the accelerators of the NICA complex. [ABSTRACT FROM AUTHOR]

Charge radii of Tl, Pb and Bi isotopic chains and magnetic moments of the Tl ground state and Tl isomeric state in thallium isotopic chain are calculated simultaneously within the self-consistent Theory of Finite Fermi Systems (TFFS) based on the Energy Density Functional DF3-a by Fayans et al. The calculated ground-state charge radii of Tl, Pb and Bi isotopic chains reveal distinctive kink at the shell closure which has a similar magnitude, as in the neighboring mercury, lead and bismuth isotopic chains. The experimental kink indicator in Tl isotopes is well described by the present calculation. Taking into account the meson exchange in the external field operator and in the effective spin dependent -interaction, as well as the regular effects of configurations and non-regular phonon-coupling (PC) corrections enables an improved description of the ground state magnetic moments in the long isotopic chain of thallium isotopes. The calculated Tl ground state magnetic moments agree fairly well with the isotopic trend reproducing the "asymmetric" jump at revealed by the recent ISOLDE (CERN) experiments. For , a "parabolic" -dependence of the Tl isomeric state magnetic moments is shown and experimental data for Tl is described without phonon-coupling corrections. [ABSTRACT FROM AUTHOR]

Using the example of the mineral magnetite, which is the main component of magnetic volcanic sand, a quantum-chemical analysis of the nature of paramagnetic properties was carried out using the molecular orbital method. Magnetic properties are among the most important characteristics of substances, and magnetic interaction is one of the fundamental forces in the universe. Understanding the chemical nature of magnetic properties allows not only to effectively use materials with magnetic properties, but also to create new materials with the desired characteristics. The magnetic properties of substances depend on their structure and elemental composition, since each charged particle inside the substance has its own magnetic moment-spin. [ABSTRACT FROM AUTHOR]

In the twenty-first century, we are witnessed of a large number of infectious ailments which spread very quickly worldwide and effect the public health significantly. Thus, in the current research, with the aim of a suitable malaria and oxidant controlling agent, micro-assay, DPPH and ABTS protocols were conducted against previously synthesized and well-characterized (mass spectrometry, NMR (1H and 13C), powder XRD, IR, electronic spectra, TGA magnetic moment, molar conductivity and SEM) hydrazone ligands (1–2) and their Co(II), Ni(II), Cu(II), Ni(II) metal complexes (3–10) of benzaldehyde derivatives and 3,5-dichlorobenzohydrazide. The biological assessment revealed that the (8), (9), (10) complexes were more potent to inhibit the malarial and oxidant infections although the complex (10) has highest ability (0.42 ± 0.05 µM for antimalaria and 1.98 ± 0.09–99 ± 0.08 µM for antioxidant) to control these diseases with comparable IC50 value to quinine and ascorbic acid. Moreover, molecular docking (against 8E1Z and 1U5A proteins), DFT and ADMET investigations were examined against the highly potent HL2 ligand and its (7–10) complexes to corroborate the acquired biological findings. The theoretical investigations also advocate the more potency of complex (10) through significant binding affinity, binding modes, hardness, softness, etc. [ABSTRACT FROM AUTHOR]

Zn‐substituted iron oxide nanoparticles of ≈5 nm in diameter are synthetized by a microwave‐assisted thermal decomposition method. The addition of ethylene glycol results in a size increase to 22 nm. Cationic disorder has been observed by electron energy loss spectroscopy–scanning transmission electron microscopy. Using Mössbauer spectrometry combined with Rietveld analysis, the complete cationic and vacancies repartition in the lattice is determined, as well as the canting of magnetic moments. This allows the magnetic moment to be calculated, in good agreement with that measured. The alternating current magnetic susceptibility is modeled by the Néel–Brown and the Coffey models, showing some discrepancy between these two approaches which is discussed. The largest particles show a complex morphology involving an oriented attachment mechanism of smaller units. Their cationic disorder and internal porosity have been evidenced and quantified, and the work shows that despite these defects they behave rather as magnetically blocked nanoparticles. [ABSTRACT FROM AUTHOR]

The rotational dynamics of the intralayer and interlayer excitons with their inherent momenta of inertia in the monolayer and bilayer transition metal dichalcogenides, respectively, where the new chirality of exciton is endowed by the rotational angular momentum, namely, the formations of left‐ and right‐handed excitons at the +K and −K valleys, respectively, is proposed. It is found that angular momenta exchange between excitons and its surrounding phononic bath result in the large fluctuation of the effective g‐factor and the asymmetry of valley Zeeman splitting observed in most recently experiments, both of which sensitively depend on the magnetic moments provided by the phononic environment. This rotating exciton model not only proposes a new controllable knob in valleytronics, but opens the door to explore the angular momentum exchange of the chiral quasiparticles with the many‐body environment. [ABSTRACT FROM AUTHOR]

AbstractA Schiff base (imine) ligand, (E)-4-((2-hydroxy-3,5-diiodobenzylidene)amino)-N-(4,6-dimethylpyrimidin-2-yl)benzenesulfonamide (HL), was synthesized by condensation of 3,5-diiodosalicylaldehyde with sulfamethazine. The ligand was then complexed with Zn(II), Cu(II), Ni(II), Co(II) and Fe(II) employing a metal to ligand ratio of 1:2 to form chelates (1-5), [M(L)2(H2O)2]. Characterization was done by UV-visible, FTIR, 1H and 13C NMR spectroscopy, elemental analysis, magnetic moments, thermogravimetric analyses (TGA) and conductance studies. The Schiff base behaved as a bidentate ligand and metal chelates assumed octahedral geometry. MOE-docking was employed to assess binding of the Schiff base (HL) and its chelates (1-5) with 1T2P, 1VVQ, 2W61, 3U2D, 4H8E and 5K18 proteins. Results indicated that Zn(II) chelate (1) and Fe(II) chelate (5) are the most potent compounds. Antibacterial and antibiofilm activities were executed against Enterococcus faecalis, Staphylococcus aureus, Proteus mirabilis and Klebsiella pneumoniae. Antifungal activities were performed against Candida albicans and Aspergillus niger. The Schiff base exhibited moderate antibacterial/antifungal activities that were enhanced on chelation with metal ions. Zinc(II) chelate (1) and Fe(II) chelate (5) show excellent antibacterial/antifungal activities. Complex 2 exhibited good antibiofilm activity. [ABSTRACT FROM AUTHOR]

A sol-gel method was employed to synthesize phase-pure (1-x)BiFeO3-xBi(Mn0.5Ti0.5)O3 (abbreviated as BFO-xBMT, x = 0–0.10) multiferroic ferrites. The investigation focused on the structure, optical, and magnetic properties, and their dependence on composition. X-ray diffraction analysis (XRD) revealed a single phase rhombohedral structure for BiFeO3 (BFO), with distinct double peaks (104)/(110) and (006)/(202) at diffraction angles 2θ ∼ 32.0° and 39.5°. As the content of Bi(Mn0.5Ti0.5)O3 (BMT) increased, a structural transition from rhombohedral (R3c) to pseudo-cubic (Pm3m) phase was observed. Doping with BMT led to a decrease in particle size. The band gap (Eg) of BFO-xBMT materials exhibited a slight increase from 1.99 eV in BFO to 2.18 eV in the BFO-0.10BMT composition. The introduction of BMT resulted in a significantly enhanced room temperature ferromagnetism in BiFeO3, with the maximum magnetic moment doubling to around 5.7 emu/g for the BFO-0.04BMT solid solution. This improvement is attributed to the addition of BMT inducing intrinsic strain in the crystal lattice, suppressing the intrinsic helical spin structure of BFO, and thus enhancing its latent magnetic potential. The research demonstrated the substantial influence of BMT perovskite on the structure, optical, and magnetic properties of BFO materials. Overall, the results suggest that the BFO-xBMT multiferroic ferrites with optimal composition hold promise for use in multifunctional devices. [ABSTRACT FROM AUTHOR]

In this work, effective modulation of the electronic and magnetic properties of Janus Si 2 PAs monolayer is proposed using vacancy engineering and doping with Ge atom. Pristine Si 2 PAs monolayer is a non-magnetic indirect gap two-dimensional (2D) material with energy gap of 1.29(2.47) eV obtained from PBE(HSE06)-based calculations. The monolayer is metallized under effects of single Si1 (bound to P atom), Si2 (bound to As atom), P, and As vacancies, preserving its non-magnetic nature. Similar effects are induced by creating P+Si1 double vacancies. Meanwhile, the diluted magnetic semiconductor nature is induced by As+Si2 and Si1+Si2 pair vacancies with total magnetic moment of 0.98 and 1.81 μ B , respectively. Herein, magnetic properties are produced mainly by As and P atoms around defect sites. Interestingly, the indirect-to-direct gap transition is achieved by doping with Ge atom at Si1 and Si2 sites, and simultaneous doping at both Si1+Si2 sites, where the energy gap exhibits only slight change. In these cases, similar valence electronic configuration of Ge and Si atoms leads to the preservation of the non-magnetic nature. In contrast, the monolayer is significantly magnetized by doping at P and As sites, as well as simultaneous doping at P+Si1 sites. Such that a total magnetic moment of 1.00 μ B is obtained, which is generated mainly by Ge impurities. The spin-polarized band structures assert the diluted magnetic semiconductor nature of these doped Si 2 PAs systems. Our results provide deep insights into the electronic properties of a new Janus Si 2 PAs monolayer, and propose efficient approaches to make potential optoelectronic and spintronic candidates from this 2D material. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) is employed based on the generalized gradient approximation (GGA), including the Hubbard (U) parameter, to investigate the modification of the electronic properties of GaN nanowires (NWs) by Eu dopants introduced via Eu‐associated defect complexes to explore the origin of magnetic characteristics. These findings show that incorporating Eu dopants, including Eu‐intrinsic defect complexes, in GaN NWs leads to a significant change in the electronic properties of GaN, as evident from p‐f state hybridization, resulting in unique magnetic characteristics. However, while Ga‐vacancies (VGa) in Eu‐doped GaN NWs impart a significant magnetic moment on N atoms, N‐vacancies (VN) produce a negligible effect on the magnetic properties of NWs. To predict the magnetic exchange effect, two Eu3+ ions are introduced in the NWs, showing that the complex with two Eu atoms and Ga‐vacancy (2Eu‐VGa) induces stable ferromagnetism above room temperature. [ABSTRACT FROM AUTHOR]

Results of the neutron powder diffraction measurements carried out for R5Pt2In4 (R = Tb–Tm) are reported. The compounds crystallize in an orthorhombic crystal structure of the Lu5Ni2In4‐type with the rare earth atoms occupying three different sublattices. Neutron diffraction data reveal that at low temperatures the rare earth magnetic moments order below the critical temperature equal to 105, 93, 28, 12 and 3.8 K for R = Tb, Dy, Ho, Er and Tm, respectively. With decreasing temperature the rare earth magnetic moments at the 2a and 4g2 sites order first, while the moments at the 4g1 site order at lower temperatures. Ferrimagnetic order along the c axis, described by the propagation vector k1 = [0, 0, 0], develops in Tb5Pt2In4 below the Curie temperature (TC = 105 K). At lower temperatures, an antiferromagnetic component in the ab plane appears. The component is incommensurate with the crystal structure (k2 = [0,0.66,½]), but it turns into a commensurate one (k3 = [0,0,½]) with decreasing temperature. Antiferromagnetic order along the c axis, described by k4 = [½,0,0], is found in Dy5Pt2In4 below the Néel temperature (TN = 93 K). The k4‐related component disappears below 80 K and the magnetic structure transforms into a ferro/ferrimagnetic one described by k1 = [0, 0, 0]. Further decrease in temperature leads to the appearance of an incommensurate antiferromagnetic component within the ab plane below 10 K (k2 = [0,0.45,½]), which finally turns into a commensurate one (k5 = [0,½,½]). In Ho5Pt2In4, a sine‐modulated magnetic structure with moments parallel to the c axis (k6 = [⅓,0,0]) is observed below 28 K. With a decrease in temperature, new components, related to k1 = [0, 0, 0] (bc plane) and k4 = [½,0,0] (c axis), appear. The coexistence of two orderings – in the ab plane (k1 = [0, 0, 0]) and a modulated one with moments along the b axis (k7 = [kx, 0, 0]) – is found in Er5Pt2In4 below 12 K. Decreasing temperature leads to the order–order transformation of the k1‐related component to another one with magnetic moments still constrained to the ab plane and preserved value of the propagation vector (i.e.k1 = [0, 0, 0]). Tm5Pt2In4 orders antiferromagnetically below TN = 3.8 K. Thulium magnetic moments lie in the ab plane, while the magnetic structure is described by k5 = [0,½,½]. The direction of magnetic moments depends on the rare earth element involved and indicates an influence of single ion anisotropy resulting from interaction with the crystalline electric field. [ABSTRACT FROM AUTHOR]

10.1119/5.0198262.1 We present a comparative investigation of two-dimensional tractor magnet configurations, analyzing both theoretical predictions and experimental results with a focus on the minimal tractor magnet. The minimal tractor magnet consists of a rigid assembly of one attracting magnet (attractor), two repelling magnets (repulsors), and a fourth magnet (follower) that is magnetically stabilized in a local energy minimum. The theoretical framework relies on magnetostatics and stability analysis of stationary equilibria. To calculate the magnetostatic force and energy, we use a multipole method. In a first approximation, we derive analytical results from the point dipole approximation. The point dipole analysis defines an upper bound criterion for the magnetic moment ratio and provides analytical expressions for stability bounds in relation to geometry parameters. Our experimental results are consistent with the predictions from the fourth-order multipole expansion. Beyond the minimal tractor magnet, we introduce a more advanced configuration that allows for a higher magnetic binding energy and follower capture at larger distances. Editor's Note: Have you heard about tractor magnets? Certain fixed arrangements of three cylindrical magnets on a tabletop surface result in a stable equilibrium for a fourth follower magnet. In this article you will find the theoretical basis for this curious stability, a thorough experimental analysis of the stability of different possible magnet arrangements, and supplementary videos and 3D printing plans so you and your students can create and study your own tractor magnets. [ABSTRACT FROM AUTHOR]

The effects of -F functional group on the structure, electronic properties and magnetic properties of Janus-type MXene 2D material CrVC were studied by first-principles of density functional theory. The calculation results indicate that the -F functional group changes the electronic properties and magnetic properties of CrVC. The nine possible structures of CrVCF2 exhibit ferromagnetic behavior, among which the structure of CrVCF2 -33 has the lowest energy and is the ground state, with a magnetic moment of 5. 01 μB and a band gap of 0. 099 eV, exhibiting semiconductor characteristics. The total magnetic moment of CrVCF2 -33 remains unchanged when - 4% - + 4% biaxial strain is applied; the energy increases with either compression or tension strain, but the change is less than 0. 2 eV; the band gap changes under the action of strain, when the tensile strain is 2. 4%, the band gap decreases to 0. 005 eV, which is close to zero. It can be considered a spin-zero band gap semiconductor. The results show that moderate strain can adjust the electronic structure of the CrVCF2 material, and it can even become a spin-zero band gap semiconductor, indicating its potential application value in the field of spintronics. [ABSTRACT FROM AUTHOR]

The chiral anomaly - a hallmark of chiral spin-1/2 Weyl fermions - is an imbalance between left- and right-moving particles that underpins phenomena such as particle decay and negative longitudinal magnetoresistance in Weyl semimetals. The discovery that chiral crystals can host higher-spin generalizations of Weyl quasiparticles without high-energy counterparts, known as multifold fermions, raises the fundamental question of whether the chiral anomaly is a more general phenomenon. Answering this question requires materials with chiral quasiparticles within a sizable energy window around the Fermi level that are unaffected by extrinsic effects such as current jetting. Here, we report the chiral anomaly of multifold fermions in CoSi, which features multifold bands within ~0.85 eV of the Fermi level. By excluding current jetting through the squeezing test, we measure an intrinsic, longitudinal negative magnetoresistance. We develop a semiclassical theory to show that the negative magnetoresistance originates in the chiral anomaly, despite a sizable and detrimental orbital magnetic moment contribution. A concomitant non-linear Hall effect supports the multifold-fermion origin of the magnetotransport. Our work confirms the chiral anomaly of higher-spin generalizations of Weyl fermions, currently inaccessible outside solid-state platforms. Multifold fermions promise a solid-state platform for accessing and studying the effects of the chiral anomaly beyond Weyl fermions. Here, the authors identify multifold fermions in magnetotransport in the chiral semimetal CoSi. [ABSTRACT FROM AUTHOR]

The effects of -F functional group on the structure, electronic properties and magnetic properties of Janus-type MXene 2D material CrVC were studied by first-principles of density functional theory. The calculation results indicate that the -F functional group changes the electronic properties and magnetic properties of CrVC. The nine possible structures of CrVCF2 exhibit ferromagnetic behavior, among which the structure of CrVCF2 -33 has the lowest energy and is the ground state, with a magnetic moment of 5. 01 μB and a band gap of 0. 099 eV, exhibiting semiconductor characteristics. The total magnetic moment of CrVCF2 -33 remains unchanged when - 4% - + 4% biaxial strain is applied; the energy increases with either compression or tension strain, but the change is less than 0. 2 eV; the band gap changes under the action of strain, when the tensile strain is 2. 4%, the band gap decreases to 0. 005 eV, which is close to zero. It can be considered a spin-zero band gap semiconductor. The results show that moderate strain can adjust the electronic structure of the CrVCF2 material, and it can even become a spin-zero band gap semiconductor, indicating its potential application value in the field of spintronics. [ABSTRACT FROM AUTHOR]

The ground state of correlated electrons in complex oxide films can be controlled by applying epitaxial strain, offering the potential to produce unexpected phenomena applicable to modern spintronic devices. In this study, we demonstrate that substrate-induced strain strongly affects the coupling mode of interfacial magnetic moments in a ferromagnetic (FM)/antiferromagnetic (AFM) system. In an epitaxial bilayer comprising AFM LaFeO3 (LFO) and FM La0.7Sr0.3MnO3 (LSMO), samples grown on a LaAlO3 (LAO) substrate exhibit a larger exchange bias field than those grown on a SrTiO3 substrate. Our results indicate a transition in the alignment of magnetic moments from perpendicular to collinear due to the large compressive strain exerted by the LAO substrate. Collinear magnetic moments at the LSMO/LFO interface generate strong exchange coupling, leading to a considerable exchange bias effect. Thus, our findings provide a method for tailoring and manipulating the orientations of magnetic moments at the FM/AFM heterogeneous interface using strain engineering, thereby augmenting methods for exchange bias generation. [ABSTRACT FROM AUTHOR]

We study the electron tunneling (ET) and local Andreev reflection (AR) processes in a quantum dot (QD) coupled to the left and right ferromagnetic leads with noncollinear ferromagnetisms. In particular, we consider that the QD is also side-coupled to a nanowire hosting Majorana bound states (MBSs) at its ends. Our results show that when one mode of the MBSs is coupled simultaneously to both spin-up and spin-down electrons on the QD, the height of the central peak is different from that if the MBS is coupled to only one spin component electrons. The ET and AR conductances, which are mediated by the dot–MBS hybridization, strongly depend on the angle between the left and right magnetic moments in the leads. Interaction between the QD and the MBSs will result in sign change of the angle-dependent tunnel magnetoresistance. This is very different from the case when the QD is coupled to regular fermonic mode, and can be used for detecting the existence of MBSs, a current challenge in condensed matter physics under extensive investigations. [ABSTRACT FROM AUTHOR]