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Exploring gate insulator materials for 2D transistors and their defect properties is of importance for device performance optimization. In this work, the structural and electronic properties of intrinsic vacancies in the CaF 2 single layer and its heterostructures with monolayer MoS 2 are investigated from first-principles calculations. V Ca introduces a shallow defect level close to the VBM, whereas V F introduces a deep level below the CBM. In both cases, spin polarization is observed. Overall, V F has a relatively lower formation energy than V Ca , except for the extreme Ca-rich case. Thus, V F should be dominant in CaF 2. The band offset between CaF 2 and MoS 2 is determined to be type-I, with large offsets at both the conduction band and valence band. With the presence of vacancies in CaF 2 , the type-I band offset is preserved. The electron or hole on the defect states will transfer from CaF 2 to MoS 2 due to the large band offset, and spin polarization vanishes. Nevertheless, there are no defect states inside the gap or around the band edge of MoS 2 , and the electronic properties of MoS 2 are almost intact. Compared with h -BN that has a small valence band offset with MoS 2 and could introduce in-gap defect states, CaF 2 can be a good candidate to serve as the dielectric layer of MoS 2 -based transistors. [ABSTRACT FROM AUTHOR]

A spintronic terahertz (THz) emitter based on rare-earth-transition-metal ferrimagnetic alloys has drawn wide attention due to its prominent THz emission signals at a magnetic compensated state. Here, THz emission spectroscopy is performed in a layered ferrimagnetic/nonmagnetic structure of Ta/Tbx(FeCo)1–x/Pt to investigate the impact of magnetization and spin polarization on THz radiation. Composition and temperature-dependent THz emission signals are observed by an inverse spin Hall effect. The variation of THz amplitude approximately follows the in-plane magnetization in the composition range, yet a nonvanishing THz radiation at the compensation point indicates that net spin polarization dominates the emitted THz electric field rather than net magnetization in this two-sublattice system. A significant gap of 90 K between the compensation point of magnetic moment and spin polarization is found in a Tb0.24(FeCo)0.76 sample, which is a striking difference to that of 25 K in GdCo/Pt THz emitters. We attribute this anomalous gap to the strong intersublattice 3d-5d6s-4f exchange interaction of TbFeCo alloy; thus, the contribution of spin polarized Tb 4f electrons should be reconsidered after fs laser pulse excitation. These results gain insight into spin dynamics of complex multisublattice systems and pave the way for further optimized spintronic THz emitters to modulate THz radiation efficiently. [ABSTRACT FROM AUTHOR]

A correlation between the spin-polarized carrier transfer and spin relaxation processes of a two-dimensional electron gas (2DEG) in an InGaN/GaN quantum well (QW) is investigated by time-resolved Kerr rotation spectroscopy at low temperature. Upon resonant excitation with the GaN barrier band edge energy, the spin polarization of the 2DEG in the QW is acquired from the transfer of spin-polarized photoexcited carriers. Significantly, the spin relaxation time of the 2DEG is enhanced to be as long as 1 ns along with the carrier transfer. It is demonstrated that by tailoring the Rashba and Dresselhaus spin–orbit couplings to approach a spin-degenerate surface, the screening effect of the polarization field leads to a longer spin relaxation time and effective manipulation of the spin relaxation. The polarization field screening induced enhancement of the spin relaxation time is significant in the way for the development of GaN-based spintronic devices. [ABSTRACT FROM AUTHOR]

Light-induced desorption of Rb atoms from a ferrimagnetic Fe 3 O 4 (001) surface was studied using a spin-selective optical method, which provides information on the spin polarization, velocity distribution, and amount of the desorbed atoms. The results showed that the intensity of the desorption of Rb from Fe 3 O 4 (001) induced by ultraviolet (UV) light irradiation was smaller than the detection limit at coverages lower than the threshold coverage at which the desorption rate began to increase. Moreover, the average magnetic quantum number of the desorbed atoms was smaller than that of electrons at the Fermi level of the Fe 3 O 4 (001) surface. These indicate that the light-induced desorption of Rb from an Fe 3 O 4 (001) surface occurs only in the high-coverage region in which the desorbing atoms are not in contact with the Fe 3 O 4 surface, and that the desorption does not involve spin transfer. [ABSTRACT FROM AUTHOR]

Tetra‐coordinated iron(II) porphyrins are observed in triplet (intermediate spin, IS) ground state with low‐lying quintet (high spin, HS) and singlet (low spin, LS) excited states. It is well known in the literature that the dFe−N bond distances are dependent on the spin state such that the dFe−N distances are larger for HS compared to the LS/IS states. This implies the existence of strong magneto‐structural correlations. Herein, the possibility to obtain the spin‐state information for a series of tetra‐coordinated square planar iron(II) porphyrin complexes have been explored by exploiting the magneto‐structural correlations obtained from first principle calculations. The spin‐state dependent nature of the chemical bonds and spin polarization on the N‐atoms play a crucial role in the vibrational dynamics of the central Fe‐atom. Theoretical nuclear resonance vibrational spectroscopy (NRVS) is adopted to investigate the vibrational dynamics and the Fe‐atom associated spectral peaks and their spin‐dependent features. We find that NRVS studies along with iron pre‐K‐edge x‐ray absorption analysis convincingly provide the information on the spin state, which could be utilized to identify the spin states without adopting any magnetic probes. [ABSTRACT FROM AUTHOR]

Highlights: Single-molecule electrical detection, especially the single-molecule junction setup, enables the precise detection and spatial operability of anchored molecules. The transition among asymmetric characteristics (i.e., molecular chirality, photonic polarization and electronic spin) is proposed as a universal methodology to realize the detection, control and synthesis of chirality. Exploring the origin of symmetry breaking contributes to the development of a general reliable strategy for asymmetric synthesis. Chirality, as the symmetric breaking of molecules, plays an essential role in physical, chemical and especially biological processes, which highlights the accurate distinction among heterochiralities as well as the precise preparation for homochirality. To this end, the well-designed structure-specific recognizer and catalysis reactor are necessitated, respectively. However, each kind of target molecules requires a custom-made chiral partner and the dynamic disorder of spatial-orientation distribution of molecules at the ensemble level leads to an inefficient protocol. In this perspective article, we developed a universal strategy capable of realizing the chirality detection and control by the external symmetry breaking based on the alignment of the molecular frame to external stimuli. Specifically, in combination with the discussion about the relationship among the chirality (molecule), spin (electron) and polarization (photon), i.e., the three natural symmetry breaking, single-molecule junctions were proposed to achieve a single-molecule/event-resolved detection and synthesis. The fixation of the molecular orientation and the CMOS-compatibility provide an efficient interface to achieve the external input of symmetry breaking. This perspective is believed to offer more efficient applications in accurate chirality detection and precise asymmetric synthesis via the close collaboration of chemists, physicists, materials scientists, and engineers. [ABSTRACT FROM AUTHOR]

To date, precisely tailoring local active sites of well‐defined earth‐abundant metal‐free carbon‐based electrocatalysts for attractive electrocatalytic oxygen reduction reaction (ORR), remains challenging. Herein, the authors successfully introduce a strain effect on active C–C bonds adjacent to edged graphitic nitrogen (N), which raises appropriate spin‐polarization and charge density of carbon active sites and kinetically favor the facilitation of O2 adsorption and the activation of O‐containing intermediates. Thus, the constructed metal‐free carbon nanoribbons (CNRs‐C) with high‐curved edges exhibit outstanding ORR activity with half‐wave potentials of 0.78 and 0.9 V in 0.5 m H2SO4 and 0.1 m KOH, respectively, overwhelming the planar one (0.52 and 0.81 V) and the N‐doped carbon sheet (0.41 and 0.71 V). Especially in acidic media, the kinetic current density (Jk) is 18 times higher than that of the planar one and the N‐doped carbon sheet. Notably, these findings show the spin polarization of the asymmetric structure by introducing a strain effect on the C–C bonds for boosting ORR. [ABSTRACT FROM AUTHOR]

Anomalous carrier transport in magnetic Heusler compounds has evolved as a lively field of research owing to their unusual band structure and broken time-reversal symmetry. They have attractive properties for spintronics due to their high Curie temperature (Tc), high spin polarization, and extravagant transport properties. Here, we scrutinize CoFeSn. Based on the inferences from structural stability, lattice dynamics, and magnetic analysis, we propose a cubic polymorph of hexagonal CoFeSn and explain why we must consider cubic CoFeSn. Through density-functional-theory calculations, we predict a robust 3D half-metallic ferromagnetic compound, CoFeSn (P 4 ¯ 3 m) with a Tc ∼ 693 K, calculated via the Heisenberg magnetic exchange interactions under mean-field approximation, and a magnetic moment of 3 μB. In addition, Wannier interpolation suggests anomalous Hall conductivity (AHC) and spin Hall conductivity (SHC) in cubic CoFeSn, the largest SHC at the Fermi level being ≈ 47 (h/2πe) S/cm. Our theoretical results show that spin–orbit interaction at the Fermi level brings on finite Berry flux that gives an intrinsic AHC ∼ 122 S/cm at room temperature. We note that adjusting the Fermi level can be a sensible way to achieve high values of AHC or SHC. Our findings pave the way for the realization of the quantum anomalous and spin Hall effect in half-Heusler compounds. [ABSTRACT FROM AUTHOR]

The chiral‐induced spin selectivity (CISS) effect relates to the spin‐selective electron transport through chiral molecules; therefore, the chiral molecules act as spin filters. In past studies, correlation was found between the magnitude of the spin filtering and the intensity of the circular dichroism (CD) spectrum (the first Compton peak) of the molecules. Since the intensity of the CD peak relates to both the magnitude of the electric and magnetic dipole transitions, it was not clear which of these properties correlate with the CISS effect. This work aims at addressing this question. By studying the spin‐dependent conduction and the CD spectra of the thiol‐functionalized enantiopure binaphthalene (BINAP) and ternaphthalene (TERNAP), we found that both BINAP and TERNAP exhibit a similar spin polarization of 50%, despite the first Compton peak in TERNAP being almost twice as intense as the peak in BINAP. These results can be explained by the similar values of their anisotropy (or dissymmetry) factor, gabs, which is proportional to the magnetic transition dipole moment. Hence, we concluded that the CISS effect is proportional to the transition dipole moment in chiral molecules, namely, to the dissymmetry factor. [ABSTRACT FROM AUTHOR]

Exploration of exotic spin polarizations in single crystals is of increasing interest. A current of longitudinal spins, the so‐called "Dresselhaus‐like" spin current, which is forbidden in materials lacking certain inversion asymmetries, is implied to be generated by a charge current at the interface of single‐crystal CoFe. This work reports unambiguous evidence that there is no indication of spin current of any spin polarizations from the interface or bulk of single‐crystalline CoFe and that the sin2φ second harmonic Hall voltage, which is previously assumed to signify Dresselhaus‐like spin current, is not related to any spin currents but rather a planar Nernst voltage induced by a longitudinal temperature gradient within the sample. Such sin2φ signal is independent of large applied magnetic fields and interfacial spin‐orbit coupling, inversely correlated to the heat capacity of the substrates and overlayers, quadratic in charge current, and appears also in polycrystalline ferromagnets. Strikingly, the planar Nernst effect (PNE) in the CoFe single crystal has a strong fourfold anisotropy and varies with the crystalline orientation. Such strong, anisotropic PNE has widespread impacts on the analyses of a variety of spintronic experiments and opens a new avenue for the development of PNE‐based thermoelectric battery and sensor applications. [ABSTRACT FROM AUTHOR]

The investigation of spin and polarization effects in ultra-high intensity laser–plasma and laser–beam interactions has become an emergent topic in high-field science recently. In this paper, we derive a relativistic kinetic description of spin-polarized plasmas, where quantum-electrodynamics effects are taken into account via Boltzmann-type collision operators under the local constant field approximation. The emergence of anomalous precession is derived from one-loop self-energy contributions in a strong background field. We are interested, in particular, in the interplay between radiation reaction effects and the spin polarization of the radiating particles. For this, we derive equations for spin-polarized quantum radiation reaction from moments of the spin-polarized kinetic equations. By comparing with the classical theory, we identify and discuss the spin-dependent radiation reaction terms and radiative contributions to spin dynamics. [ABSTRACT FROM AUTHOR]

Equiprobable incoherent mixtures of two totally polarized states of light whose associated three-dimensional Jones vectors are mutually orthogonal are called discriminating states and constitute a peculiar type of state that plays a key role in the characteristic decomposition of a generic state into a totally polarized state, a totally unpolarized state, and a discriminating state. In general, discriminating states are three-dimensional, in the sense that the strengths of the three components of the electric field are nonzero for any Cartesian reference frame considered. In the limiting case that the electric field evolves in a fixed plane, the discriminating state is said to be regular and corresponds to a two-dimensional unpolarized state. The special features of discriminating states cover, e.g., their possible synthesis from infinite pairs of mutually orthogonal states as well as their transverse spin. The nature and properties of discriminating states are comprehensively analyzed based on their associated intrinsic Stokes parameters, which leads to meaningful interpretations in terms of the associated polarization ellipsoids and spin vectors. [ABSTRACT FROM AUTHOR]

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The low separation efficiency of the photogenerated carrier and the poor activity of the surface redox reaction are the main barrier to further improvement of photocatalytic materials. To address these issues, introducing spin‐polarized electrons in single‐component photocatalytic materials emerged as a promising approach. However, the decreased redox ability of photocarriers in these materials becomes a new challenge. Herein, we mitigate this challenge with a carbon nitride sheet (CNs)/graphene nanoribbon (GNR) composite material that has a van der Waals heterostructures (vdWHs) and spin‐polarized electron properties. Experimental results and theoretical calculations show that the heterostructure has a strong redox ability, high carrier‐separation efficiency, and enhanced surface catalytic reaction. Consequently, the mixed‐dimensional CNs/GNR vdWHs exhibit remarkable performance for H2 and O2 generation as well as CO2 production under visible‐light irradiation without any cocatalyst. The spin‐polarized vdWHs discovered in this study revealed a new type of photocatalytic materials and advanced the development of spintronics and photocatalysis. [ABSTRACT FROM AUTHOR]

Conservation of polarization is an important requirement for reliable single-photon emitters, which, in turn, are essential building blocks for light-based quantum information processing. In this work, we study the exciton-spin dynamics in a double quantum dot under the combined effects of electron-hole exchange and Förster resonance energy transfer. By means of numerical solutions of the quantum master equation, we simulate the time-dependent spin polarization for two neighboring dots. According to our results, under some conditions, the depolarization caused by the electron-hole exchange may be slowed by the near field-induced interdot energy transfer, suggesting a new mechanism to extend the exciton coherence time. This opens doors to alternative schemes for improved solid-state quantum light sources. [ABSTRACT FROM AUTHOR]

The electron tunneling in ZnO/ZnCdO semiconductor heterostructure is studied using the matrix method. The spin-polarization is examined due to Dresselhaus spin–orbit interaction and Rashba spin–orbit interaction. The total spin-polarization is mainly due to Dresselhaus spin–orbit interaction and the Rashba spin–orbit interaction is small. The high degree of spin polarization can be achieved at a high barrier width. With the increasing cadmium concentration in this heterostructure, the spin polarization efficiency is enhanced. The dwell time is reported and discussed. [ABSTRACT FROM AUTHOR]

In this paper, the structural, electronic, magnetic, and half-metallic properties of full-Heusler alloys Mn2ZrX (X = As , Bi) in the Hg2CuTi-type structure have been studied by using the first-principles-based density functional theory (DFT) with the full-potential linearized augmented plane-wave (FP-LAPW) method. Mn2ZrX (X = As , Bi) compounds are found to be half-metallic ferrimagnets. The calculated total magnetic moments of the Mn2ZrX (X = As , Bi) alloys are estimated at 01 μ B according to the Slater–Pauling rule of M tot = ( Z tot –24) μ B . It was discovered that Mn2ZrAs and Mn2ZrBi maintained their half-metallicity for a lattice constant interval of 5.72 to 6.26 Å and 6.33 to 6.62 Å, respectively, and present a maximum degree of spin polarization at the Fermi level. In addition, the predicted formation energy and elastic parameters show that these materials are mechanically stable. All of these results indicate that these new Mn2-based heusler alloys are able to be the candidates for spintronic applications. [ABSTRACT FROM AUTHOR]

Many textbook physical effects in crystals are enabled by some specific symmetries. In contrast to such 'apparent effects', 'hidden effect X' refers to the general condition where the nominal global system symmetry would disallow the effect X, whereas the symmetry of local sectors within the crystal would enable effect X. Known examples include the hidden Rashba and/or hidden Dresselhaus spin polarization that require spin-orbit coupling, but unlike their apparent counterparts are demonstrated to exist in non-magnetic systems even in inversion-symmetric crystals. Here, we discuss hidden spin polarization effect in collinear antiferromagnets without the requirement for spin-orbit coupling (SOC). Symmetry analysis suggests that antiferromagnets hosting such effect can be classified into six types depending on the global vs local symmetry. We identify which of the possible collinear antiferromagnetic compounds will harbor such hidden polarization and validate these symmetry enabling predictions with first-principles density functional calculations for several representative compounds. This will boost the theoretical and experimental efforts in finding new spin-polarized materials. A hidden effect can occur in materials where locally a symmetry is broken, even though global symmetry is preserved. An example is hidden spin-polarization, arising from local inversion symmetry breaking in otherwise globally centro-symmetric materials. Here, Yuan et al uncover a hidden spin-polarization that can occur in antiferromagnets without spin-orbit coupling and identify the key material requirements for this to occur. [ABSTRACT FROM AUTHOR]

The two degenerate valleys in transition metal dichalcogenides can be used to store and process information for quantum information science and technology. A major challenge is maintaining valley polarization at room temperature where phonon-induced intervalley scattering is prominent. Here we demonstrate room temperature valley polarization in heterostructures of monolayer MoS2 and naphthylethylammine based one-dimensional chiral lead halide perovskite. By optically exciting the heterostructures with linearly polarized light close to resonance and measuring the helicity resolved photoluminescence, we obtain a degree of polarization of up to −7% and 8% in MoS2/right-handed (R-(+)-) and left-handed (S-(-)-) 1-(1-naphthyl)ethylammonium lead iodide perovskite, respectively. We attribute this to spin selective charge transfer from MoS2 to the chiral perovskites, where the perovskites act as a spin filter due to their chiral nature. Our study provides a simple, yet robust route to obtain room temperature valley polarization, paving the way for practical valleytronics devices. Valleytronics is a portmanteau of 'valley' and 'electronics' and refers to the use of the valley degree of freedom, present in some materials, for encoding and processing information. Here, Shrestha et al demonstrate a room temperature valley polarization in heterostructures composed of molybdenum disulfide and a chiral lead halide perovskite, an important step in development of valleytronics. [ABSTRACT FROM AUTHOR]

The relativistic inverse spin Hall effect (ISHE) plays a pivotal role in terahertz (THz) emission in magnet/heavy metal bilayers. Here, THz emission from RuO2/Py bilayers is reported due to not only the relativistic ISHE but also the nonrelativistic inverse altermagnetic spin splitting effect (IASSE) in RuO2. For the (100)‐oriented RuO2/Py bilayers, the THz emission is greatly enhanced owing to IASSE once the polarization direction of the spin current (from the Py layer induced by pump laser) is parallel to the Néel vector of RuO2, producing the anisotropic THz emission with twofold symmetry. In contrast, the RuO2(110)/Py bilayer only exhibits isotropic THz emission because of the absence of IASSE‐induced spin‐charge conversion in the (110)‐oriented RuO2 films. Apart from the fundamental significance of exploring the IASSE‐induced spin‐to‐charge conversion, the finding also enriches the physical mechanism and modulation method of THz emission in spintronic systems. [ABSTRACT FROM AUTHOR]

The relativistic inverse spin Hall effect (ISHE) plays a pivotal role in terahertz (THz) emission in magnet/heavy metal bilayers. Here, THz emission from RuO2/Py bilayers is reported due to not only the relativistic ISHE but also the nonrelativistic inverse altermagnetic spin splitting effect (IASSE) in RuO2. For the (100)‐oriented RuO2/Py bilayers, the THz emission is greatly enhanced owing to IASSE once the polarization direction of the spin current (from the Py layer induced by pump laser) is parallel to the Néel vector of RuO2, producing the anisotropic THz emission with twofold symmetry. In contrast, the RuO2(110)/Py bilayer only exhibits isotropic THz emission because of the absence of IASSE‐induced spin‐charge conversion in the (110)‐oriented RuO2 films. Apart from the fundamental significance of exploring the IASSE‐induced spin‐to‐charge conversion, the finding also enriches the physical mechanism and modulation method of THz emission in spintronic systems. [ABSTRACT FROM AUTHOR]

Inspired by potential application prospects of spintronics and valleytronics, a novel heterobilayer Janus structure is designed by replacing the chalcogenide atomic layers in the original bilayer MoS2. Based on first-principles calculations, it is found that the SMoS/SeMoS structure exhibits a direct band-gap semiconductor and a typical type-II band alignment with longer carrier lifetime. The transition metal (TM) atom represented by V/Cr/Mn can be stably adsorbed on the heterobilayer Janus SMoS/SeMoS sheet and effectively introduce magnetic moments (m). The calculation results demonstrate that the most stable adsorption site of the TM atom is CX(A), and the TM (V/Cr/Mn) adatom modified SMoS/SeMoS system is converted into metal (V-) or half-metal (Cr/Mn-), respectively. Under the coupling of different indirect exchange interactions, the structure exhibits stable intrinsic anti-ferromagnetic interactions for V-SMoS/SeMoS and ferromagnetic ground state for Cr/Mn-SMoS/SeMoS, respectively, and the magnetic transition temperature (T c) reaches a high temperature or even room temperature. Moreover, the robust out-of-plane magnetocrystalline anisotropy energy ensures stable long-range magnetic order. Specifically, the combination of spin injection and strong spin–orbit coupling interaction effectively breaks the time-reversal symmetry, which leads to valley polarization of the system. Based on this, the biaxial strain can effectively regulate the electronic structure, magnetic properties and valley polarization of TM-SMoS/SeMoS nanosheets with double breaking of spatial-inversion and time-reversal symmetry. [ABSTRACT FROM AUTHOR]

A possibility of generating a high degree of spin polarization of 13C and 15N nuclei in the cyanide ion, which forms the coordination bond with the metal ion, using parahydrogen is demonstrated for the first time for the new iridium carbene complex as an example. The spin–spin interaction constants in the synthesized complex and the structure of the hydride intermediate are determined by an analysis of the 13С NMR spectra detected using broadband and selective heteronuclear decoupling. The cyanide ion is shown to coordinate to the metal ion by the carbon atom in one of two equatorial positions, and two pyridine molecules are arranged in the axial and equatorial positions. The signal amplification factors for 13С and 15N nuclei of the cyanide anion (5665 and –49 555, respectively) are estimated by NMR spectroscopy of the polarized substrate using the SABRE method from an ultralow magnetic field of 0.5 μT. This amplification corresponds to 15.5% polarization of nitrogen nuclei achieved within several seconds at room temperature. [ABSTRACT FROM AUTHOR]

Physical characteristics of quaternary Heusler alloys (QHAs) FeNbYZ (Z = Al, Ga, In, Sn) are determined using full potential linearized augmented plane wave (FP-LAPW) method within the framework of density functional theory (DFT) by implying generalized gradient approximation (GGA) and Perdew-Burke-Ernzerhof (PBE) exchange potential. First of all, structural stability is investigated to find the most optimized structure. The geometry optimization results indicated that the third type has the most stable structure among other two types along with ferromagnetic (FM) phase stability. The calculated band structures (BS) and density of states (DOS) indicated that these QHAs are half metals (HMs) having bang gap at only spin down channel. The computed magnetic moments (MMs) of FeNbYAl, FeNbYGa, FeNbYSn and FeNbYIn are compared with the MMs that obtained from Slater Pauling rule (SPR). These materials being totally spin polarization (SP) (i.e., 100%) had high Curie temperature (Tc) and high MM showing them half metallic nature and good to be used in useful applications. The mechanical stability is determined by computing elastic constants, bulk modulus, Young modulus, hardness, and Poisson ratio. The findings of mechanical attributes deduce that all investigated QHAs are ductile and had Pugh's ratio > 1.75 making these materials mechanically stable. Furthermore, the calculations of thermoelectric properties have shown that these alloys could be utilized as thermoelectric in addition to spintronics. [ABSTRACT FROM AUTHOR]

We present the observation of field-free spin-orbit-torque (SOT) switching of magnetization in a ferromagnetic semiconductor (Ga,Mn)As film with four-fold in-plane magnetic anisotropy. Magnetization switching is demonstrated between two orthogonal in-plane easy axes through planar Hall resistance measurements as a current is scanned in the absence of a magnetic field. The chirality of the switching of the current hysteresis loop is consistent with SOT arising from spin polarization caused by Dresselhaus- and Rashba-type spin-orbit-induced effective magnetic fields in the (Ga,Mn)As film. The chirality of magnetization switching can be reversed either by changing the direction of the initial magnetization or by applying a constant external magnetic field bias. The SOT magnetization switching between two states was consistently repeated by applying sequential current pluses with alternating polarities, indicating the potential for developing a field-free SOT device. [ABSTRACT FROM AUTHOR]

To meet the current requirements of diluted magnetic semiconductors (DMSs) resulting from continuous advancements in spintronics, designing d0 DMSs with high stability, spin polarization, and Curie temperature is essential. Present research on introducing d0 magnetism is limited to monatomic doping, lacking regulation measures for local magnetic moments and long range magnetic coupling. Herein, an adjacent doping strategy is employed to introduce degrees of freedom for tuning the magnetic properties of d0 DMSs. It is observed that by introducing Si and O atoms as central and adjacent dopants, respectively, the intrinsically nonmagnetic hexagonal boron nitride (h-BN) exhibits significant local magnetic moments. Furthermore, it is observed that the ionization energy, total magnetic moment, magnetic coupling, and Curie temperature of the doped h-BN are susceptible to the Si–O coordination. Subsequently, a magnetic half-metal (Si–O3-doped h-BN) with high thermal stability, 100% spin polarization, long range ferromagnetic coupling, and high Curie temperature is designed through high Si–O coordination doping. This study proposes a feasible approach for introducing tunable d0 magnetism using the design of Si–O adjacent-doped h-BN as an example. [ABSTRACT FROM AUTHOR]

2D magnetic van der Waals (vdW) junctions have attracted intensive attention due to their easily controllable thickness and clear interface compared to conventional magnetic multilayer films, which provide a perfect platform to control the performance of spintronic devices. Herein, based on the experimentally fabricated FeCl2 flaks with interlayer antiferromagnetism and intralayer ferromagnetism, we explore the spin transport properties of two classes of vdW junctions with an Au electrode, Au/FeCl2/Au (FeCl2 as the tunnel barrier) and Au/FeCl2/barrier/FeCl2/Au (MoS2 or graphene as the tunnel barrier), and focus on the effects of different barriers and the number of layers. It is found that from monolayer to bilayer FeCl2 in Au/FeCl2/Au, the spin filtering effect is considerably increased due to the weakened interface effect, and almost complete spin polarized current can be obtained. For Au/FeCl2/MoS2/FeCl2/Au, whether the number of layers of MoS2 or FeCl2 is increased from monolayer to bilayer, the tunnel magnetoresistance (TMR) becomes higher due to the high spin polarization of FeCl2, which can reach 1 374 000%. The high TMR of 763 000% can also be achieved for Au/FeCl2/graphene/FeCl2/Au. This work suggests potential applications for FeCl2 flaks in 2D vdW spin filters and spin valves and will stimulate broad studies on layer- and barrier-controllable vdW spintronic devices. All calculations are performed by using the first-principles combined with non-equilibrium Green's function method. [ABSTRACT FROM AUTHOR]

Standard relativistic hydrodynamics has been successful in describing the properties of the strongly interacting matter produced in the heavy-ion collision experiments. Recently, there has been a significant theoretical advancement in this field to explain spin polarization of hadrons emitted in these processes. Although current models have successfully explained some of the experimental data based on the coupling between spin polarization and vorticity of the medium, they still lack a clear understanding of the differential measurements. This is commonly interpreted as an indication that the spin needs to be treated as an independent degree of freedom whose dynamics is not entirely bound to flow circulation. In particular, if the spin is a macroscopic property of the system, in equilibrium its dynamics should follow hydrodynamic laws. Here, we develop a framework of relativistic hydrodynamics which includes spin degrees of freedom from the quantum kinetic theory for Dirac fermions and use it for modeling the dynamics of matter. Following experimental observations, we assume that the polarization effects are small and derive conservation laws for the net baryon current, the energy–momentum tensor and the spin tensor based on the de Groot–van Leeuwen–van Weert definitions of these currents. We present various properties of the spin polarization tensor and its components, analyze the propagation properties of the spin polarization components, and derive the spin-wave velocity for arbitrary statistics. We find that only the transverse spin components propagate, analogously to the electromagnetic waves. Finally, using our framework, we study the space–time evolution of the spin polarization for the systems respecting certain space–time symmetries and calculate the mean spin polarization per particle, which can be compared to the experimental data. We find that, for some observables, our spin polarization results agree qualitatively with the experimental findings and other model calculations. [ABSTRACT FROM AUTHOR]

Multi-directional spin-to-charge conversion—in which spin polarizations with different orientations can be converted into a charge current in the same direction—has been demonstrated in low-symmetry materials and interfaces. This is possible because, in these systems, spin-to-charge conversion can occur in unconventional configurations in which charge current, spin current, and polarization do not need to be mutually orthogonal. Here, we explore, in the low temperature regime, the spin-to-charge conversion in heterostructures of graphene with the low-symmetry 1T' phase of MoTe2. First, we observe the emergence of charge conversion for out-of-plane spins at temperatures below 100 K. This unconventional component is allowed by the symmetries of both MoTe2 and graphene and likely arises from spin Hall effect in the spin–orbit proximitized graphene. Moreover, we examine the low-temperature evolution of non-local voltage signals arising from the charge conversion of the two in-plane spin polarizations, which have been previously observed at higher temperature. As a result, we report omni-directional spin-to-charge conversion—for all spin polarization orientations—in graphene/MoTe2 heterostructures at low temperatures. [ABSTRACT FROM AUTHOR]

We propose a method of cooling nuclear spin systems of solid-state nanostructures by applying a time-dependent magnetic field synchronized with spin fluctuations. Optical spin noise spectroscopy is considered a method of fluctuation control. Depending on the mutual orientation of the oscillating magnetic field and the probe light beam, cooling might be either provided by dynamic spin polarization in an external static field or result from population transfer between spin levels without build-up of a net magnetic moment ("true cooling"). [ABSTRACT FROM AUTHOR]

The structural, electronic, magnetic, and optical properties of MFe2O4 (M = Ni, Fe, Co) ferrites were investigated by employing Cambridge Serial Total Energy Package code using density functional theory. LDA+U was used to investigate the structural, electronic, magnetic, and optical properties of MFe2O4 (M = Ni, Fe, Co) ferrites at different pressures 0, 5, 10, 15, and 20 GPa. The simulated X‐ray diffraction (XRD) pattern of MFe2O4 (M = Ni, Fe, Co) ferrites was investigated and the computed lattice parameters decreased 8.62–8.32, 8.68–8.35, and 8.567–8.267 Å at 0–20 GPa, respectively. XRD revealed that the unit cell's volumes (640.50–575.93, 653.97–582.182, 627.22–563.550), X‐ray densities (4.86–5.40, 4.70–5.28, 3.97–4.43), and interatomic distance (2.6099–2.5180, 2.6221–2.4260, 2.5831–2.4928) of MFe2O4 (M = Ni, Fe, Co) ferrites were also decreased with the increasing pressure 0–20 GPa, respectively. The LDA+U calculations predicted that the NiFe2O4, Fe3O4, and CoFe2O4 ferrite followed the properties of a semiconductor exhibiting a direct band gap of 1.2, 1.13, and 0.710 eV at 0 GPa which were decreased to 0.846, 0.710, and 0.461 eV at 20 GPa, respectively. The computed density of states revealed that MFe2O4 (M = Ni, Fe, Co) ferrites exhibited good spin polarization behavior, and Ni–O, Fe–O, and Co–O bonds were covalent. The Mullikens investigated the ted decrease in bong length of MFe2O4 (M = Ni, Fe, Co) ferrites versus 0–20 GPa as well as according to Hirschfeld analysis the magnetic moment (3.348–3.335, 4.12–4.10, 3.737–3.735) and saturation magnetization (79.06–78.7, 99.33–98.9, 88.93–88.352) of MFe2O4 (M = Ni, Fe, Co) ferrites were decreased with increased pressure 0–20 GPa, respectively. The reflectivity and absorption specialize in visible and ultraviolet regions showing their stability for optoelectronics, photocatalysis, and solar cell applications. [ABSTRACT FROM AUTHOR]

Chiral‐induced spin selectivity is recently demonstrated in a range of spin‐dependent optoelectronics and electrochemistry. Herein, a new type of amorphous chiral tartaric acid‐FeNi coordination polymer fabricated by electrodeposition methods, achieving both high spin‐polarization and high electrocatalytic activity for oxygen evolution, is reported. Circular dichroism shows signature optical activity from the coordination polymer. Conductive atomic force microscopy measurements demonstrate a high spin polarization through the chiral electrocatalyst, which significantly suppresses the formation of hydrogen peroxide byproducts compared to the achiral ones. These chiral Fe‐Ni electrocatalysts exhibit a low overpotential of 205 and 280 mV to achieve 10 and 100 mA cm−2, respectively. [ABSTRACT FROM AUTHOR]

Electrical manipulation of magnetization without an external magnetic field is critical for the development of advanced non-volatile magnetic-memory technology that can achieve high memory density and low energy consumption. Several recent studies have revealed efficient out-of-plane spin-orbit torques (SOTs) in a variety of materials for field-free type-z SOT switching. Here, we report on the corresponding type-x configuration, showing significant in-plane unconventional spin polarizations from sputtered ultrathin [Pt/Co]N, which are either highly textured on single crystalline MgO substrates or randomly textured on SiO2 coated Si substrates. The unconventional spin currents generated in the low-dimensional Co films result from the strong orbital magnetic moment, which has been observed by X-ray magnetic circular dichroism (XMCD) measurement. The x-polarized spin torque efficiency reaches up to −0.083 and favors complete field-free switching of CoFeB magnetized along the in-plane charge current direction. Micromagnetic simulations additionally demonstrate its lower switching current than type-y switching, especially in narrow current pulses. Our work provides additional pathways for electrical manipulation of spintronic devices in the pursuit of high-speed, high-density, and low-energy non-volatile memory. Spin-orbit torques, arising in systems with strong spin-orbit interactions, have been a major avenue of research for the potential electric control of magnetization. Recently, unconventional spin-orbit torques, with spin polarizations aligned in atypical ways have garnered interest due to the numerous advantages offered compared to their conventional counterparts. Here, Xue et al investigate 'type-x' spin-orbit torque switching, demonstrating both unique spin polarizations, and field-free magnetization switching in Platinum/Cobalt multilayers. [ABSTRACT FROM AUTHOR]

Spin- and angle-resolved photoemission spectroscopy (SARPES) with high efficiency and resolution plays a crucial role in exploring the fine spin-resolved band structures of quantum materials. Here, we report the performance of the SARPES instrument with a second-generation home-made multichannel very-low-energy-electron-diffraction spin polarimeter. Its energy and angular resolutions achieve 7.2 meV and 0.52°, respectively. We present the results of SARPES measurements of Bi(111) film to demonstrate its performance. Combined with the density functional theory calculations, the spin polarization of the bulk states was confirmed by the spin-layer locking caused by the local inversion asymmetry. The surface states at a binding energy of 0.77 eV are found with 1.0 ± 0.11 spin polarization. Better resolutions and stability compared with the first-generation one provide a good platform to investigate the spin-polarized electronic states in materials. [ABSTRACT FROM AUTHOR]

Both Ti2FeGe and CoTiFeGe compounds were designed based on density functional theory within GGA and mBJ-GGA approximations. Lattice parameter optimization in ferromagnetic and nonmagnetic phases for XA type structures were done in order to predict the magnetic stable ground state. The calculated total energy indicates that the most stable phase of XA type ordering is ferromagnetic state. The band structure and density of states for XA type ordering for the studied alloys exhibit half-metallic nature using GGA and mBJ-GGA approaches that is a precursor for high spin polarization in those alloys. Except for Ti2FeGe alloy, which exhibits metallic character when we used mBJ-GGA method. The calculated energy bands indicate that Ti2FeGe (CoTiFeGe) is an indirect band gap and the value of gap is 0.606 eV (0.490 eV) using GGA scheme and it is 0.00 eV (0.982 eV) by mBJ-GGA method. The elastic properties, such as stability, hardness, stiffness, ductility and brittleness were explored and determined by simulated elastic constants. The anisotropy of the stable compounds Ti2FeGe and CoTiFeGe have values in 3.79 and 2:73, respectively. Also, the Ti2FeGe and CoTiFeGe compounds follow the necessary Slater–Pauling rule conditions Mtot = NV-18 and Mtot = NV-24 for half-metallicity and they have a total magnetic moment of 2 µB and 1 µB, respectively. Their optical properties have confirmed semiconducting behavior and their main optical response occurs in the infrared (IR) and visible ranges and the very low loss in the same region, along with existence absorption, make them as suitable for optoelectronic applications for novel infrared (IR) detector devices. The substitution by Co led to a slight blue shift of the optical peaks. [ABSTRACT FROM AUTHOR]

We study the impact of the QCD critical point (CP) on the spin polarization of Λ -hyperon generated by the thermal vorticity in viscous quark gluon plasma (QGP). The equations of the relativistic causal viscous hydrodynamics have been solved numerically in (3+1) dimensions to evaluate the thermal vorticity. The effects of the CP have been incorporated through the equation of state (EoS) and the scaling behavior of the transport coefficients. We observe a significant suppression of the spin polarization around mid-rapidity region induced by the CP and propose that such changed behaviour of the spin polarization can be used to detect the CP. To the best of our knowledge this is the first study on the effects of critical point on the spin polarization in QCD matter. [ABSTRACT FROM AUTHOR]

Using the first-principles calculations based on density functional theory (DFT) within the generalized gradient approximation (GGA), Ti2RuAl full-Heusler compound is studied. The electronic structure, magnetic, and optical properties of Ti2-based full Heusler compound Ti2RuAl are calculated and analyzed using the Wien2k package. The CuHg2Ti-type structure is found to be more favorable than the AlCu2Mn-type structure for this compound. The Ti2RuAl Heusler compound exhibits a ferrimagnetic half-metallic behavior with the total magnetic moment of 1 µB at the equilibrium lattice constant 6.24 Å. The total magnetic moment of Ti2RuAl is in agreement with the Slater-Pauling rule mtot = ztot–18 and hence has integral magnetic moments which is due to 100% spin polarization at Fermi energy. Ti2RuAl has an energy gap in the spin-down channel of 0.229 eV. This compound keeps a 100% of spin polarization for lattice constant change in the range of 5.8–6.5 Å. The Curie temperature of Ti2RuAl is estimated to be 451 K using the mean field approximation (MFA). In addition, optical properties like dielectric function, reflectivity, energy loss function, absorption coefficient, and optical conductivity are calculated. [ABSTRACT FROM AUTHOR]

The structural, elastic, electronic, and magnetic properties of the CrCoSi, MnCoSi parent half-Heusler (HH) alloys, and their CrMnCo2Si2 derivative double half-Heusler (DHH) compound are studied, utilizing the augmented plane wave method, which is based on density functional theory and implemented in the WIEN2k code. The stability of HH structure of the CrCoSi and MnCoSi alloys has been checked for their non-magnetic and ferromagnetic phases, leading to that the latter phase of the type I arrangement is the most stable. The CrMnCo2Si2 DHH alloy, derivative from the found structural and magnetic ground states of CrCoSi and MnCoSi HH alloys, is constructed and investigated. This DDH as well as its CrCoSi parent HH are found to be resistant to deformation and can be classified as ductile materials, whereas the MnCoSi compound is brittle. By the gradient generalized approximation (GGA), the electronic structures of CrCoSi, MnCoSi, and CrMnCo2Si2compounds exhibit a metallic behavior in the spin-up channel and a semiconducting behavior in the spin-dn channel, with band gaps (half-metallic gaps) of 0.851(0.020), 0.852(0.021), and 0.531(0.002) eV, respectively. The half-metallicity of CrMnCo2Si2 DHH is retained with smaller (larger) band gap (half-metallic gap) of 0.38(0.106) eV than that of GGA, using GGA + U approximation. In addition, the total magnetic moments are found to be 1, 2, and 3 µB for CrCoSi, MnCoSi, and CrMnCo2Si2, respectively. Therefore, these alloys can be good candidates for spinitronic applications due to their half-metallicity. [ABSTRACT FROM AUTHOR]

The study of heterogeneous reactions for enantiomeric processes based on inorganic crystals has been resurgent in recent years. However, the question remains how homochirality develops in nature and chemical reactions. Here, the successful growth of B20 group PdGa single crystals with different chiral lattices enabled us to achieve enantioselective recognition of 3,4‐dihydroxyphenylalanine (DOPA) based on a new mechanism, namely orbital angular momentum (OAM) polarization. The orbital textures of PdGa crystals indicate large OAM polarization near the Fermi level and carrying opposite signs. A positive or negative magnetization in the [111] direction is expected depending on the chiral lattice of PdGa crystals. Due to this, the adsorption energies of PdGa crystals and DOPA molecules differ depending on how well the O‐2p orbital of DOPA pairs with the Pd‐4d orbital of PdGa. The results provide one possible explanation for how chirality arises in nature by providing an enantioselective route with pure inorganic crystals. [ABSTRACT FROM AUTHOR]

A subclass of ternary intermetallic known as Heusler compounds is being employed in the steel industry to increase material strength. This study examines the structural, electrical, optical, and magnetic properties of Co2VZ (Z=Al, Bi, Ge, Si) compounds using two different methods. First is full potential linearized augmented plane wave (FP-LAPW) method by WIEN2k and second is pseudo potential method by Atomic Tool Kit-Virtual Nano-Lab. The equivalent energy gaps in the minority-spin of Co2VZ (Z= Al, Bi, Ga, Ge) with WIEN2k code, which displays 100% spin polarization, are 0.703, 0.384, 0.186, and 0.67 eV near to the Fermi level. Furthermore, it is discovered that these compounds are absolutely half-metallic ferromagnetic (HMF). With the exception of Co2VBi, which exhibits metallic properties, the aforementioned compounds exhibit 0.525, 0.0, 0.553, and 0.786 eV band gaps in the ATK-VNL code and indicate 100% spin polarization. The magnetic moments of the compounds Co2VZ (Z= Al, Bi, Ga, Ge) are found to be 2.976, 4.003, 1.989, and 3.001 µB, respectively, in the WIEN2k code. The relative magnetic moments of the aforementioned compounds are also 1.991, 3.947, 1.999, and 2.997 µB, according to the ATK-VNL code. [ABSTRACT FROM AUTHOR]

Herein, the spin‐polarized edge‐state transport properties in L‐shaped zigzag MoS2$\left(\text{MoS}\right)_{2}$ nanodevice (L-zMoS2ND$\left(\text{L�?zMoS}\right)_{2} \text{ND}$) are investigated based on tight‐binding model, Green's function method, and ballistic transport theory. The spin conductance and spin polarization are calculated by considering external exchange field and electric field. It is shown in the results that the spin conductance is closely related to the configuration of atomic non‐consistence on the edge of L-zMoS2ND$\left(\text{L�?zMoS}\right)_{2} \text{ND}$. Meanwhile, the spin conductance is determined by the spin channel opening on the edge, which can be modulated by external fields. The configuration characteristic and external fields give rise to effects of sublattice mismatch and spin mismatch on the edge channels, respectively. As a consequence, mismatch effects are actually employed to modulate the spin channel on the edge of L-zMoS2ND$\left(\text{L�?zMoS}\right)_{2} \text{ND}$, and 100% spin polarization is realized selectively. Moreover, the corresponding local density of states distributions are plotted to reveal the modulation of the spin‐resolved edge‐state and the spin‐filtering effects in the real space. These spin‐polarized edge‐state transport properties in L-zMoS2ND$\left(\text{L�?zMoS}\right)_{2} \text{ND}$ can have potential application in various kinds of spin valves and spin filters in nanocircuits. [ABSTRACT FROM AUTHOR]

Density functional theory in the framework of generalized gradient approximation (GGA) of Perdew–Burke–Ernzerhof to investigate the effects of some selected transition metal (TM) and rare‐earth metal (RE) dopants on the electronic and magnetic properties of a 2D molybdenum disulfide (MoS2) monolayer is reported. The results demonstrate that it is energetically stable to incorporate Ni and Cu in MoS2 structure under Mo‐rich conditions. The pristine MoS2 monolayer has a calculated direct bandgap of 1.70 eV and experiences significant reduction in the gap due to the defects. There is observed induced magnetic behavior due to the tight binding effect originating from the localized dopants and the nearest‐neighbor Mo atoms, with magnetic moments ranging between 0.82 and 3.00 μB. Some of the dopants result in 100%$$ spin polarization which is useful for engineering spin filter devices on magnetic MoS2 nanostructures. [ABSTRACT FROM AUTHOR]

The structural, elastic, electronic, and magnetic properties of the CrCoSi, MnCoSi parent half-Heusler (HH) alloys, and their CrMnCo2Si2 derivative double half-Heusler (DHH) compound are studied, utilizing the augmented plane wave method, which is based on density functional theory and implemented in the WIEN2k code. The stability of HH structure of the CrCoSi and MnCoSi alloys has been checked for their non-magnetic and ferromagnetic phases, leading to that the latter phase of the type I arrangement is the most stable. The CrMnCo2Si2 DHH alloy, derivative from the found structural and magnetic ground states of CrCoSi and MnCoSi HH alloys, is constructed and investigated. This DDH as well as its CrCoSi parent HH are found to be resistant to deformation and can be classified as ductile materials, whereas the MnCoSi compound is brittle. By the gradient generalized approximation (GGA), the electronic structures of CrCoSi, MnCoSi, and CrMnCo2Si2compounds exhibit a metallic behavior in the spin-up channel and a semiconducting behavior in the spin-dn channel, with band gaps (half-metallic gaps) of 0.851(0.020), 0.852(0.021), and 0.531(0.002) eV, respectively. The half-metallicity of CrMnCo2Si2 DHH is retained with smaller (larger) band gap (half-metallic gap) of 0.38(0.106) eV than that of GGA, using GGA + U approximation. In addition, the total magnetic moments are found to be 1, 2, and 3 µB for CrCoSi, MnCoSi, and CrMnCo2Si2, respectively. Therefore, these alloys can be good candidates for spinitronic applications due to their half-metallicity. [ABSTRACT FROM AUTHOR]

The employment of spin polarization under an external magnetic field holds great potential for the improvements of photocatalytic performance. However, owing to the huge difference in dielectric properties between ferromagnetic oxide and polymers, the photogenerated excitons with spin states are often limited to the ferromagnetic oxide wells, which leads to unsatisfactory activity. In this paper, a single-atom Co-doped C3N4 photocatalyst is successfully synthesized for photocatalytic water splitting and simultaneous oxidation of benzylamine. Under a tiny external magnetic field (24.5 mT), the hydrogen production rate could reach at 3979.0 µmol·g−1·h−1, which is about 340 times that of C3N4. Experimental results and theoretical calculations indicate that the interaction of Co d and N p orbital changes the symmetry center of C3N4, resulting in an increase in dielectric constant and spin polarization. Moreover, magnetic fields further promote parallel electron spin, and the increased number of charges with the parallel spin-down state is likely to dissociate under the action of an external magnetic field. On the other hand, the Co-N bond provides a huge built-in electric field and active site for strengthening the charge transfer and surface reaction. This work not only deepens the understanding of spin polarization, but also enriches methods to accelerate electron-hole separation. [ABSTRACT FROM AUTHOR]

Analysis of ponderomotive effects exciting from propagation of an intense laser pulse through high density quantum plasma under the influence of an axial magnetic field taking into consideration the spin–spin (up and down) exchange interaction. The effects of electron Fermi pressure, quantum Bohm potential, and electron spin have been included in the analysis. Spin polarization is a result of the concentration difference of opposite spin electrons which is produced under the influence of the applied magnetic field. Axial gradient of the ponderomotive potential of laser has been applied for the electron acceleration. An analytic solution of the electron energy gain is obtained and the influence of spin polarization is analyzed both numerically and analytically. It is observed that spin polarization, density perturbation and the magnetic field effect electron acceleration dramatically. Further, the effect of nonlinearity on the refractive index of plasma has been studied. [ABSTRACT FROM AUTHOR]

In contrast to diradical linked by π-conjugation, there have been only a limited number of studies reported for those linked by homoconjugation systems. Bis(nitronyl nitroxide) diradicals and monoradical connected by a core non-rigid triptycene unit were synthesized. EPR spectroscopy and SQUID were employed to investigate the magnetic exchange interactions. The results demonstrate that the values of ΔEST are 0.19 kcal/mol (J = 34.4 cm−1) for 2,6-TP-NN and −0.21 kcal/mol (J = −36.9 cm−1) for 2,7-TP-NN, indicating ferromagnetic interaction and antiferromagnetic interaction, respectively. The spin polarization rule is not a precise predictor of the behavior of triptycene diradicals, and therefore, we improve the model. The experimental findings indicate that homoconjugation can function directly as a coupling pathway between the two spin centers, which is in qualitative agreement with the DFT theoretical calculations and the Borden rule. This research has found a special means of achieving spin coupling in non-rigid aromatics by means of homoconjugation. [ABSTRACT FROM AUTHOR]

A systematic structure and property investigation of MnGen− (n = 3–14) was conducted by means of density functional theory coupled with mass-selected anion photoelectron spectroscopy. This combined theoretical and experimental study allows global minimum and coexistence structures to be identified. It is found that the pentagonal bipyramid shape is the basic framework for the nascent growth process of MnGen− (n = 3–10), and from n = 10, the endohedral structures can be found. For n = 12, the anion MnGe12− cluster probably includes two isomers: a major isomer with a puckered hexagonal prism geometry and a minor isomer with a distorted icosahedron geometry. Specifically, the puckered hexagonal prism isomer follows the Wade–Mingos rules and can be suggested as a new kind of superatom with the magnetic property. Furthermore, the results of adaptive natural density partitioning and deformation density analyses suggest a polar covalent interaction between Ge and Mn for endohedral clusters of MnGe12−. The spin density and natural population analysis indicate that MnGen− clusters have high magnetic moments localized on Mn. The density of states diagram visually shows the significant spin polarization for endohedral structures and reveals the weak interaction between the Ge 4p orbital and the 4s, 3d orbitals of Mn. [ABSTRACT FROM AUTHOR]

Several proposals are available to get selective spin transmission through different nano-junctions and in all the cases the regulation is done either by applying a magnetic field or by tuning spin–orbit (SO) coupling. In the present work, we explore a separate scheme where the spin-dependent transport is regulated externally by irradiating a quantum ring that bridges the contact electrodes. This is a new proposal of generating spin selective transmission through a nano-junction, to the best of our knowledge. A high degree of spin polarization along with its phase alteration can be achieved by suitably adjusting the irradiation, circumventing the regulation of magnetic field and/or SO coupling. The effect of irradiation is included through the well-known Floquet-Bloch ansatz, where all the spin-dependent transport phenomena are worked out using Green's function formalism following the Landauer–Büttiker prescription within a tight-binding framework. Precise dependencies of light irradiation, SO coupling, magnetic flux threaded by the ring, interface sensitivity, system temperature, and impurities on spin polarization are critically investigated. Our analysis may give a new platform for spin selective electron transmission and make it applicable to other complex nano-structured materials also. We strongly believe that the present proposal can be examined in a suitable laboratory. [ABSTRACT FROM AUTHOR]