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The three-nucleon force (3NF) is crucial in shaping the shell structure of atomic nuclei, particularly impacting the enhancement of spin-orbit (SO) splitting, especially in nuclei with significant deviations from stability. Despite its importance, the specific mechanisms driving this enhancement remain unclear. In this study, we introduce a decomposition scheme based on the rank of irreducible tensors forming the 3NF, derived from chiral effective field theory at next-to-next-to-leading order, to elucidate their influence on SO splitting. Within the shell-model framework, our analysis reveals that the rank-1 component of the 3NF is the primary factor enlarging the energy gap between the 0p3/2 and 0p1/2 single-particle levels in p-shell nuclei, while the rank-2 component makes a subdominant contribution. Since the rank-1 component originates exclusively from the 2π-exchange 3NF, our finding will not depend on the choice of the low-energy constants of contact terms. We also remark on the antisymmetry of the rank-1 3NF, which can affect the quantum entanglement of spin states. This study lays the groundwork for further exploration into this field toward a microscopic understanding of the 3NF impact on the nuclear shell structure.

Intercalation of noble metals can produce giant Rashba-type spin–orbit splittings in graphene. The spin–orbit splitting of more than 100 meV has yet to be achieved in graphene on metal or semiconductor substrates. Here, we report the p-type graphene obtained by Pt intercalation of zero-layer graphene on SiC substrate. The spin splitting of ∼200 meV was observed at a wide range of binding energies. Comparing the results of theoretical studies of different models with the experimental ones measured by spin-ARPES, XPS and STM methods, we concluded that inducing giant spin–orbit splitting requires not only a relatively close distance between graphene and Pt layer but also the presence of graphene corrugation caused by a non-flat Pt layer. This makes it possible to find a compromise between strong hybridization and increased spin–orbit interaction. In our case, the Pt submonolayer possesses nanometer-scale lateral ordering under graphene. [ABSTRACT FROM AUTHOR]

[Display omitted] • The influence of spin–orbit interaction on band structure of platinum nanotubes is shown using linearized augmented cylindrical waves method. • The ballistic transport of electrons in nanotubes is assessed. • The electron density with different spin at Fermi level is calculated for ideal nanotubes and under torsional deformation conditions. Using Density Functional Theory based on the plane wave method and linearized augmented cylindrical wave method, and taking into account the spin–orbit interaction, the structural, electronic and spin properties of ultrathin single-walled nanotubes consisting of six platinum rows are obtained. The nanotubes are found to possess metallic electronic mobility, including the nonchiral Pt(6,0) with the largest number (15 G 0) of ballistic channels. Analysis of the density of electronic states at Fermi level revealed that the chiral Pt(5,1) has a difference in concentration of mobile electrons with opposite spins of 1.42 times, and up to 3–4 times under a weak torsional strain. [ABSTRACT FROM AUTHOR]

We present an efficient and low-scaling implementation of a density functional theory based method for the computation of electronic g-tensors. It allows for an accurate description of spin-orbit coupling effects by employing the spin-orbit mean-field operator. Gauge-origin independence is ensured by the use of gauge-including atomic orbitals. Asymptotically linear scaling with molecule size is achieved with an atomic orbital based formulation, integral screening methods, and sparse linear algebra. In addition, we introduce an ansatz that exploits the locality of the contributions to the g-tensor for molecules with local spin density. For such systems, sublinear scaling is obtained by restricting the magnetic field perturbation to the relevant subspaces of the full atomic orbital space; several criteria for selecting these subspaces are discussed and compared. It is shown that the computational cost of g-tensor calculations with the local approach can fall below the cost of the self-consistent field calculation for large molecules. The presented methods thus enable efficient, accurate, and gauge-origin independent computations of electronic g-tensors of large molecular systems. [ABSTRACT FROM AUTHOR]

This study has systematically investigated the atomic number (Z) dependence of spectra from gallium-like (Ga-like) ions of heavy elements. We have mainly analyzed the experimental spectra recorded in high-temperature plasmas produced in the Large Helical Device (LHD) for various elements with atomic numbers from 57 onward. The measured wavelengths are compared with theoretical values calculated with a multi-configuration Dirac Fock code. As a result, we have successfully obtained Z-dependent wavelengths of several prominent transitions of Ga-like ions, including a magnetic dipole (M1) transition. Many of them have been experimentally identified for the first time in this study. The present results manifest the significant effects of configuration interaction and spin–orbit interaction for highly charged heavy ions. [ABSTRACT FROM AUTHOR]

High-resolution anion photoelectron spectra of cryogenically cooled C7− and C9− clusters obtained using slow photoelectron velocity-map imaging are presented, providing insight into the vibronic structure of neutral C7 and C9. These spectra yield accurate measurements of vibrational frequencies for the neutral clusters as well as electron affinities of 3.3517(4) and 3.6766(14) eV for C7 and C9, respectively. In the C7− spectrum, transitions involving the previously unreported v1 and v2 symmetric stretching modes, as well as the v9, v10, and v11 asymmetric bending modes, are assigned. Spin–orbit splitting is observed for several transitions in this spectrum, giving an energy difference of 28(6) cm−1 between the Π 1 / 2 g 2 and Π 3 / 2 g 2 spin–orbit levels of the C7− anion. In the spectrum of C9−, transitions involving the previously unreported symmetric stretch v1 and the asymmetric bend v11 are observed. In both spectra, several features are assigned to Franck-Condon forbidden transitions involving the doubly degenerate v10 and v11 modes of C7 and the v13 and v14 modes of C9. The appearance of these transitions is attributed to Herzberg-Teller coupling between the electronic states of the neutral clusters. Additional FC-forbidden transitions to states previously observed in gas-phase infrared experiments are observed and attributed to vibronic coupling between the electronic states of the anion, resulting in non-totally symmetric character in the anion's full vibrational ground state. Finally, consideration of the energy dependence of detachment cross sections and Dyson orbital analyses reveal that addition of more carbon atoms to the linear chain results in photodetachment from delocalized molecular orbitals with increasing nodal structure, leading to threshold photodetachment cross sections that differ considerably from simple symmetry considerations. [ABSTRACT FROM AUTHOR]

We present a state interaction spin-orbit coupling method to calculate electron paramagnetic resonance g-tensors from density matrix renormalization group wavefunctions. We apply the technique to compute g-tensors for the TiF3 and CuCl 4 2 − complexes, a [2Fe–2S] model of the active center of ferredoxins, and a Mn4CaO5 model of the S2 state of the oxygen evolving complex. These calculations raise the prospects of determining g-tensors in multireference calculations with a large number of open shells. [ABSTRACT FROM AUTHOR]

Photoreflectance (PR) and photoreflectance excitation (PRE) techniques are employed to investigate the optical properties of the GaAs1-xBix(x=0%–3.7%)/GaAs heterostructure grown by molecular beam epitaxy. The relations between broadenings and intensities of E0 and E0+ ΔSo transitions in PR as a function of Bi content are disclosed. Both PR and PRE experimental techniques independently show that the oscillator strength of the E0+ ΔSo transition becomes larger compared to that of the fundamental gap as the Bi content increases. Such results suggest that the incorporation of Bi into GaAs leads to an increase of the effective masses for the spin-orbit split-off band. [ABSTRACT FROM AUTHOR]

In this work, we show that domain wall (DW) dynamics within a system provide an alternative platform to characterizing spin-orbit torque (SOT) effective fields. In perpendicularly magnetized wires with a Pt/(Co/Ni)4/Co/IrMn stack structure, differential Kerr imaging shows that the magnetization switching process is via the nucleation of the embryo state followed by domain wall propagation. By probing the current induced DW motion in the presence of in-plane field, the SOT effective fields are obtained using the harmonic Hall voltage scheme. The effective anisotropy field of the structure decreases by 12% due to the SOT effective fields, as the in-plane current in the wire is increased. [ABSTRACT FROM AUTHOR]

The structural, functional and thermal properties of the TeZnCaB glass system were investigated in this work. The thermal properties of the glass system were studied using DSC (differential scanning calorimetry), and the glass transition temperature (Tg) decreased from 470 °C to 438 °C with increasing TeO 2 concentration. The vibrational and bending modes of the TeZnCaB glass samples were depicted by Raman spectroscopy analysis. FTIR (Fourier-transform infrared spectroscopy) was performed to investigate the functional groups of TeO 2 and B 2 O 3 in the samples. The TeZnCaB glass samples consist of TeO 3 , TeO 4 , BO 4 and BO 3 structural units. XPS (X-ray photoelectron spectroscopy) was investigated to reveal information about the chemical environment and the creation of NBO (non-bridging oxygen) and BO (bridging oxygen) for the different glass systems. The high-resolution Te3d spectrum confirms the presence of various tellurium-based structural units such as TeO 4 , TeO 3 , and TeO 3+1. The deconvolution of B1s spectra confirmed the existence of two forms of boron (B) such as BO 4 (four coordination) and BO 3 (three coordination) in the TeZnCaB glass system. • Raman spectroscopy confirmed the presence of Te–O–Te linkages, TeO 3 and TeO 4 vibrations in the TeZnCaB glass system. • FTIR analysis revealed B–O stretching vibrations in BO 3 and BO 4 units and O–H stretching in hydroxyl groups. • Glass transition temperatures (Tg) ranged from 438 °C to 470 °C and decreased with increasing TeO 2 concentration. • XPS analysis indicated the presence of different Te structural units such as TeO 4 , TeO 3 , and TeO 3+1 , and revealed two forms of boron (B) such as BO 4 and BO 3. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDs) possess intrinsic spin–orbit interaction (SOI) with high potential to be exploited for various quantum phenomena. SOI allows the manipulation of spin degree of freedom by controlling the carrier's orbital motion via mechanical strain. Here, strain modulated spin dynamics in bilayer MoS2 field‐effect transistors (FETs) fabricated on crested substrates are demonstrated. Weak antilocalization (WAL) is observed at moderate carrier concentrations, indicating additional spin relaxation path caused by strain fields arising from substrate crests. The spin lifetime is found to be inversely proportional to the momentum relaxation time, which follows the Dyakonov–Perel spin relaxation mechanism. Moreover, the spin–orbit splitting is obtained as 37.5 ± 1.4 meV, an order of magnitude larger than the theoretical prediction for monolayer MoS2, suggesting the strain enhanced spin‐lattice coupling. The work demonstrates strain engineering as a promising approach to manipulate spin degree of freedom toward new functional quantum devices. [ABSTRACT FROM AUTHOR]

We report our spectroscopic studies of the d 3Π state of ultra-cold 7Li85Rb using resonantly enhanced multi-photon ionization and depletion spectroscopy with bound-to-bound transitions originating from the metastable a ³Σ+ state. We evaluate the potential of this state for use as the intermediate state in a stimulated-Raman-adiabatic-passage transfer scheme from triplet Feshbach LiRb molecules to the X ¹&#931+ ground state and find that the lowest several vibrational levels possess the requisite overlap with initial and final states, as well as convenient energies. Using depletion measurements, we measured the well depth and spin-orbit splitting. We suggest possible pathways for short-range photoassociation using deeply bound vibrational levels of this electronic state. [ABSTRACT FROM AUTHOR]

Unstrained Ge1-xSnx layers of various Sn concentration (1.5%, 3%, 6% Sn) and Ge0.97Sn0.03 layers with built-in compressive (ε=-0.5%) and tensile (ε=0.3%) strain are grown by molecular beam epitaxy and studied by electromodulation spectroscopy (i.e., contactless electroreflectance and photo-reflectance (PR)). In order to obtain unstrained GeSn layers and layers with different built-in in-plane strains, virtual InGaAs substrates of different compositions are grown prior to the deposition of GeSn layers. For unstrained Ge1-xSnx layers, the pressure coefficient for the direct band gap transition is determined from PR measurements at various hydrostatic pressures to be 12.2±0.2meV/kbar, which is very close to the pressure coefficient for the direct band gap transition in Ge (12.9 meV/kbar). This suggests that the hydrostatic deformation potentials typical of Ge can be applied to describe the pressure-induced changes in the electronic band structure of Ge1-xSnx alloys with low Sn concentrations. The same conclusion is derived for the uniaxial deformation potential, which describes the splitting between heavy-hole (HH) and light-hole (LH) bands as well as the strain-related shift of the spin-orbit (SO) split-off band. It is observed that the HH, LH, and SO related transitions shift due to compressive and tensile strain according to the Bir-Pikus theory. The dispersions of HH, LH, and SO bands are calculated for compressive and tensile strained Ge0.97Sn0.03 with the 8-band kp Hamiltonian including strain effects, and the mixing of HH and LH bands is discussed. In addition, the dispersion of the electronic band structure is calculated for unstrained Ge1-xSnx layers (3% and 6% Sn) at high hydrostatic pressure with the 8-band kp Hamiltonian, and the pressure-induced changes in the electronic band structure are discussed. [ABSTRACT FROM AUTHOR]

This study has systematically investigated the atomic number (Z) dependence of spectra from gallium-like (Ga-like) ions of heavy elements. We have mainly analyzed the experimental spectra recorded in high-temperature plasmas produced in the Large Helical Device (LHD) for various elements with atomic numbers from 57 onward. The measured wavelengths are compared with theoretical values calculated with a multi-configuration Dirac Fock code. As a result, we have successfully obtained Z-dependent wavelengths of several prominent transitions of Ga-like ions, including a magnetic dipole (M1) transition. Many of them have been experimentally identified for the first time in this study. The present results manifest the significant effects of configuration interaction and spin–orbit interaction for highly charged heavy ions.

We have measured depletion spectra of the heteronuclear (85Rb87Rb+) dimer cation complexed with up to 10 He atoms. Two absorption bands are observed between 920 and 250 nm. The transition into the repulsive 12Σu+ state of HeRb2+ gives rise to a broad feature at 790 nm (12,650 cm−1); it exhibits a blueshift of 98 cm−1 per added He atom. The transition into the bound 12Πu state of HeRb2+ reveals vibrational structure with a band head at ≤ 15,522 cm−1, a harmonic constant of 26 cm−1, and a spin–orbit splitting of ≤ 183 cm−1. The band experiences an average redshift of − 38 cm−1 per added He atom. Ab initio calculations rationalize the shape of the spectra and spectral shifts with respect to the number of helium atoms attached. For a higher number of solvating helium atoms, symmetric solvation on both ends of the Rb2+ ion is predicted. [ABSTRACT FROM AUTHOR]

The evolution of the traditional nuclear magic numbers away from the valley of stability is an active field of research. Experimental efforts focus on providing key spectroscopic information that will shed light into the structure of exotic nuclei and understanding the driving mechanism behind the shell evolution. In this work, we investigate the Z=6 spin-orbit shell gap towards the neutron dripline. To do so, we employed NA(p,2p)CA−1 quasi-free scattering reactions to measure the proton component of the 21+ state of 16,18,20C. The experimental findings support the notion of a moderate reduction of the proton 1p1/2−1p3/2 spin-orbit splitting, at variance to recent claims for a prevalent Z=6 magic number towards the neutron dripline.

The kinetic-energy dependence of the Re+ + O2 reaction is examined using guided ion-beam mass spectrometry. The cross section for ReO+ formation from ground state Re+ (7S) is unusual, exhibiting two endothermic features. The kinetic energy dependence for ReO+ formation is analyzed to determine D0(Re+-O) = 4.82 ± 0.05 eV, with the higher energy feature having a threshold 1.35 ± 0.28 eV higher in energy. This bond energy is consistent with much less precise values determined in the literature. Formation of ReO2+ is also observed with a pressure dependent cross section, establishing that it is formed in an exothermic reaction of ReO+ with O2. The nature of the bonding for ReO+ and ReO2+ is discussed and analyzed primarily using theoretical calculations at the B3LYP/def2-TZVPPD level of theory. The ground state of ReO+ is identified as either 5Π or 3Δ, with the latter favored once estimates of spin-orbit splitting are included. Bond energies for ground state ReO+ are calculated at this level as well as BP86 and CCSD(T,full) levels using several different basis sets. BP86 theoretical bond energies are higher than the experimental value, whereas B3LYP and CCSD(T,full) values are lower, although estimated spin-orbit corrections increase the latter close to experiment. Potential energy surfaces for the reaction of Re+ with O2 are also calculated at the B3LYP/def2-TZVPPD level of theory and reveal that ground state Re+ (7S) inserts into O2 by forming a Re+(O2) (5A″) complex which can then couple with additional surfaces to form ground state ReO2+ (3B1). Several explanations for the unusual dual endothermic features are explored, with no unambiguous explanation being evident. As such, this heavy metal system provides a very interesting experimental phenomenon of both adiabatic and nonadiabatic behavior. [ABSTRACT FROM AUTHOR]

The effect of electron spin-orbit interactions on chemical reaction dynamics has been a topic of much research interest. Here we report a combined experimental and theoretical study on the effect of electron spin and orbital angular momentum in the F + HD → HF + D reaction. Using a high-resolution imaging technique, we observed a peculiar horseshoe-shaped pattern in the product rotational-state– resolved differential cross sections around the forward-scattering direction. The unusual dynamics pattern could only be explained properly by highly accurate quantum dynamics theory when full spin-orbit characteristics were considered. Theoretical analysis revealed that the horseshoe pattern was largely the result of quantum interference between spin-orbit split–partial-wave resonances with positive and negative parities, providing a distinctive example of how spin-orbit interaction can effectively influence reaction dynamics. [ABSTRACT FROM AUTHOR]

The newly synthesized phosphorus‐ and arsenic‐containing analogues of the thio‐ and seleno‐cyanate anions, PCSe−, AsCS−, and AsCSe−, as well as the known ion NCSe− were investigated in the gas phase by negative‐ion photoelectron spectroscopy (NIPES), velocity‐map imaging (VMI) spectroscopy, and quantum‐chemical computations. The electron affinities (EA), spin–orbit (SO) splittings, and "symmetric"/"asymmetric" stretching frequencies of the neutral radicals ECX. (E=N, P, As; X=S, Se), generated by electron detachment from the corresponding anions, were obtained from the spectra. The calculated EAs, SO splittings, and vibrational frequencies are in excellent agreement with the experimental measurements. These newly obtained values, when combined with those previously determined for the lighter analogues, show interesting trends on descending the pnictogen and chalcogen series. These trends are rationalized based on electronegativity arguments, the electron distributions in the HOMOs, and NBO/NRT analyses. [ABSTRACT FROM AUTHOR]

Abstract Spin-orbit splitting of conduction band in HgTe quantum wells was studied experimentally. In order to recognize the role of different mechanisms, we carried out detailed measurements of the Shubnikov-de Haas oscillations in gated structures with a quantum well widths from 8 to 18 nm over a wide range of electron density. With increasing electron density controlled by the gate voltage, splitting of the maximum of the oscillation Fourier spectrum f 0 into two components f 1 and f 2 and the appearance of the low-frequency component f 3 was observed. Our analysis shows that the components f 1 and f 2 are determined by the electron densities n 1 and n 2 in spin-orbit split subbands while the f 3 component results from magneto-intersubband oscillations so that it is determined by the difference between these densities Δ n. This allows us to obtain all three values n 1 , n 2 and Δ n independently. Comparison of the data obtained with results of self-consistent calculations carried out within the framework of four-band kP model shows that the main contribution to spin-orbit splitting comes from the Bychkov-Rashba effect. Contribution of the interface inversion asymmetry to the splitting of the conduction band turns out to be four-to-five times less than that for the valence band in the same structures. Highlights • Spin-orbit splitting of the electron spectrum in HgTe quantum wells are studied over a wide range of electron density. • The main contribution to the splitting comes from the Bychkov-Rashba effect while the contribution of the interface inverse asymmetry is much less. • The interface inverse asymmetry does not contribute to the splitting of the conduction band unlike the valence band. [ABSTRACT FROM AUTHOR]

Abstract The band structure of free Bi(111) films is studied by means of full-relativistic density functional theory calculations. A single free Bi(111) bilayer with optimized lattice constant a = 4.19 Å is found to be semiconducting both in semirelativistic and full-relativistic calculations, i.e. without and with accounting for spin–orbit coupling (SOC), respectively. With increases of a up to the related bulk value, 4.53 Å, the gap decreases down to ∼0.06 eV. For a up to 4.60 Å the band gap, calculated with SOC is significantly less than that without SOC, meaning that SOC does not open the gap, but, in contrast, decreases it. For the bilayer with a = 4.70 Å the situation is opposite and the gap opens just due to SOC. For larger a , free Bi(111) bilayers are semiconducting regardless of accounting for SOC. Thicker films, built from several Bi(111) bilayers, in contrast, acquire semimetallic properties. It is suggested therefore that the metallicity of Bi slabs stems from the interaction between Bi bilayers but not from surface states. A hydrogen monolayer, adsorbed on one face of the Bi(111) film, leads to the appearance of spin–orbit splitting of the bands. For clean Bi(111) slabs, the splitting is absent, which means that the existence of the surface itself cannot initiate the required break of inversion symmetry. Highlights • A free Bi bilayer is a semiconductor regardless of the lattice period. • Metallicity of Bi films stems from the interaction between bilayers. • One monolayer of H leads to metallization of the Bi(111) bilayer. • Spin–orbit splitting of bands initiates from an H monolayer on one face of the bilayer. • Spin–orbit splitting is absent for a clean Bi(111) film. [ABSTRACT FROM AUTHOR]

Silicon whiskers with doping concentration of 2 × 1018 cm–3 were chosen to investigate magnetoconductance in the range of 0-14 T at cryogenic temperatures under compressive strain up to – 2 × 10–3 rel. un. The whiskers were doped with boron during the growth process by chemical vapor deposition method, and the concentration of charge carriers, according to Hall studies, was about 2 × 1018 cm–3. The uniaxial strain of whiskers was carried out by fixing them to the substrates using thermal strain due to the difference between the coefficients of thermal expansion of the crystal and the substrate material. Longitudinal magnetoresistance for unstrained and strained Si whiskers was studied in the temperature range of 4.2 ÷ 70 K. The unstrained whiskers have a quadratic dependence of the magnetoresistance on the magnetic field induction. The strain leads to the appearance of negative magnetoresistance with sufficiently large magnitude (up to 15 %). The possible reasons of the effect were discussed. The most probable reason of negative magnetoresistance appearance is weak localization (WL) of the charge carriers. According to calculations within the WL model, the coherence length Lφ and spin-orbit length Lso are proportional to T−0.53 and T−0.45, respectively. The latter one is closed to T−1/2 expected from the theoretical data for a twodimensional system. This fact is the evidence of the conclusion that conductance in Si whiskers mostly occurs in the subsurface layers of crystals. Strain influence on spin-orbit splitting and the valence band spectrum was studied. As a result, the splitting of light and heavy hole branches was found under compressive strain according to the k-p-method. The spin splitting energy for sub-band of heavy holes ▵SO was found to be 1.8 meV. [ABSTRACT FROM AUTHOR]

The intrachain magnetic interaction and the electronic structure of Sr3NiIrO6 are investigated by performing the first-principles density functional calculations. The results show that the interaction between Ir and Ni is antiferromagnetic in each quasi-one-dimensional chain. More importantly, the GGA+U calculations hardly reproduce the insulating characteristics of Sr3NiIrO6 in the region of reasonable correlation parameter. Interestingly, the spin-orbit coupling (SOC) together with the electron-electron correlation (GGA+SOC+U) can lead to the insulating characteristics of Sr3NiIrO6. This provides apparent evidence that Sr3NiIrO6 belongs to a new category of insulator: SOC induced Mott insulator. [ABSTRACT FROM AUTHOR]

The intrachain magnetic interaction and the electronic structure of Sr3NiIrO6 are investigated by performing the first-principles density functional calculations. The results show that the interaction between Ir and Ni is antiferromagnetic in each quasi-one-dimensional chain. More importantly, the GGA+U calculations hardly reproduce the insulating characteristics of Sr3NiIrO6 in the region of reasonable correlation parameter. Interestingly, the spin-orbit coupling (SOC) together with the electron-electron correlation (GGA+SOC+U) can lead to the insulating characteristics of Sr3NiIrO6. This provides apparent evidence that Sr3NiIrO6 belongs to a new category of insulator: SOC induced Mott insulator. [ABSTRACT FROM AUTHOR]

Abstract Using the relativistic Hartree–Fock Lagrangian PKA1, we investigate the properties of the exotic nucleus 48Si, which is predicted to be an atypical nucleus characterized by i) the onset of doubly magicity, ii) its location at the drip line, iii) the presence of dual semi-bubble structure (distinct central depletion in both of neutron and proton density profiles) in the ground state, and iv) the occurrence of pairing reentrance at finite temperature. While not being new for each, these phenomena are found to simultaneously occur in 48Si. For instance, the dual semi-bubble structure reduces the spin–orbit splitting of low- ℓ orbitals and upraises the s orbitals, leading therefore to distinct N = 34 and Z = 14 magic shells in 48Si. Consequently, the doubly magicities provide extra stability for such extreme neutron-rich system at the drip line. Associating with the neutron shell N = 34 and continuum above, the pairing correlations are reengaged interestingly at finite temperature. Theoretical nuclear modelings are known to be poorly predictive in general, and we asset our confidence in the prediction of our modeling on the fact that the predictions of PKA1 in various regions of the nuclear chart have systematically been found correct and more specifically in the region of pf shell. Whether our predictions are confirmed or not, 48Si provides a concrete benchmark for the understanding of the nature of nuclear force. [ABSTRACT FROM AUTHOR]

The pulsed-field-ionisation zero-kinetic-energy photoelectron spectrum of the origin band of the ionising transition of propyne has been recorded at a resolution sufficient to partially resolve the rotational structure. The rovibronic photoionisation selection rules are derived in the spin double group C3v(MS)2 and are used to model the experimental spectrum and determine the adiabatic ionisation energy of propyne and the spin-orbit coupling constant of the radical cation of propyne. The Jahn-Teller effect is found to significantly affect the spin-orbit splitting of the cationic ground state. [ABSTRACT FROM AUTHOR]

Valence band anticrossing (VBAC) model is used to investigate band structure of InNBi, GaNBi and AlNBi for the purpose of optimal performance group-III nitride related devices. Obvious reduction in band gap and increase in spin-orbit splitting energy are founded by doping dilute concentration of bismuth in all these III-N material. The band gap of GaNBi and AlNBi show a step change, and this can be explained by the special position relation between of Bi impurity energy level with corresponding host's band offsets. We also show how bismuth may be used to form alloys by finding the doping region which can provide a means of suppressing non-radiative CHSH (hot-hole producing) Auger recombination and inter-valence band absorption. For InNBi, bismuth concentration beyond 1.25% is found to be corresponding to the range of and it shows a continuous adjustable band gap from 0.7 eV to zero. This may make InNBi a potential candidate for near or mid-infrared optoelectronic applications. [ABSTRACT FROM AUTHOR]

We measured the photoelectron spectra of diatomic AuSi- and AuGe- and conducted calculations on the structures and electronic properties of AuSi-/0 and AuGe-/0. The calculations at the CASSCF/CASPT2 level confirmed that experimentally observed spectra features of AuSi- and AuGe- can be attributed to the transitions from the 3Σ- anionic ground state to the 2Π (2Π1/2 and 2Π3/2), 4Σ-, 32Σ+, and 42Σ+ electronic states of their neutral counterparts. The electron affinities (EAs) of AuSi and AuGe are determined by the experiments to be 1.54 ± 0.05 and 1.51 ± 0.05 eV, respectively. The spin-orbit splittings (2Π1/2-2Π3/2) of AuSi and AuGe measured in this work are in agreement with the literature values. The energy difference between the 4Σ- (A) and 2Π1/2 states of AuSi obtained in this work is in reasonable agreement with the literature value, while that of AuGe obtained in this work by anion photoelectron spectroscopy is slightly larger than the literature value by neutral emission spectroscopy. The term energies of the 32Σ+ (B) and 42Σ + (C) states of AuSi and AuGe were also determined based on the photoelectron spectra. Because of the different bond lengths between the anionic and neutral states, the electronic state terms energies of AuSi and AuGe estimated from the anion photoelectron spectra might be slightly different from those obtained from the neutral emission spectra. [ABSTRACT FROM AUTHOR]

The electronic structure of Fe adsorbed g-C 2 N with different layers is investigated by first-principles calculations. The Fe 1 and Fe 2 represent the Fe adsorptions at C C and C N rings, and Fe 11 and Fe 121 adsorption sites are also considered. The Fe 1 adsorbed g-C 2 N is metallic with layer from n  = 1 to 4, and the maximum spin splitting is 515, 428, 46 and 133 meV. The band gap of Fe 2 adsorbed g-C 2 N with different layers is 0, 0, 117 and 6 meV, and the maximum spin splitting is 565, 369, 195 and 146 meV, respectively. All of the Fe 11 adsorbed g-C 2 N are metallic with layer from n  = 1 to 4, and the maximum spin splitting is 199, 0, 83 and 203 meV. An indirect band gap of 215 meV appears in Fe 121 adsorbed g-C 2 N at layer n  = 3, and the maximum spin splitting is 283, 211, 304 and 153 meV, respectively. Our results show that the electronic structures of Fe adsorbed novel two-dimensional semiconductor g-C 2 N can be tuned by different layers. Moreover, the spin splitting of Fe 2 adsorbed g-C 2 N decreases monotonically as g-C 2 N layer increases from n  = 1 to 4, which will provide more potential applications in spintronic devices. [ABSTRACT FROM AUTHOR]

A systematic and specific pattern due to the effects of the tensor forces is found in the evolution of spin–orbit splittings in neutron drops. This result is obtained from relativistic Brueckner–Hartree–Fock theory using the bare nucleon–nucleon interaction. It forms an important guide for future microscopic derivations of relativistic and nonrelativistic nuclear energy density functionals. [ABSTRACT FROM AUTHOR]

Spin–orbit torque (SOT) originates from the spin–orbit interaction of non-magnetic heavy metals (HMs), allowing for an electrical manipulation of perpendicular magnetization in HM/ferromagnet (FM)/oxide structures. In this paper, we experimentally demonstrate the SOT-induced switching of two FM bits addressed with a single write line. We fabricate a device consisting of two perpendicularly magnetized Ta/CoFeB/MgO structures with a common Ta underlayer, in which the magnetization directions of the two FM bits could be concurrently controlled by injecting a single current pulse. This suggests that multiple bits in SOT-based devices can be written as either “0” or “1” at the same time. Moreover, the selective switching of a specific bit is achieved by differentiating the critical switching currents between the two FM bits, which is crucial in demonstrating multi-level cell SOT memory. Our results provide an efficient writing mechanism, enabling wider applications of SOT-based spintronic devices. [ABSTRACT FROM AUTHOR]

Theoretical investigations are carried out to determine the temperature dependence of the local structural parameters of Cr 3+ and Mn 2+ ions doped into RAl 3 (BO 3 ) 4 (RAB, R = Y, Eu, Tm) crystals. The zero-field splitting (ZFS) parameters (ZFSPs) obtained from the spin Hamiltonian (SH) analysis of EMR (EPR) spectra serve for fine-tuning the theoretically predicted ZFSPs obtained using the semi-empirical superposition model (SPM). The SPM analysis enables to determine the local structure changes around Cr 3+ and Mn 2+ centers in RAB crystals and explain the observed temperature dependence of the ZFSPs. The local monoclinic C 2 site symmetry of all Al sites in YAB necessitates consideration of one non-zero monoclinic ZFSP (in the Stevens notation, b 2 1 ) for Cr 3+ ions. However, the experimental second-rank ZFSPs ( D = b 2 0 , E = 1 / 3 b 2 2 ) were expressed in a nominal principal axis system. To provide additional insight into low symmetry aspects, the distortions (ligand's distances Δ R i and angular distortions Δ θ i ) have been varied while preserving monoclinic site symmetry, in such way as to obtain the calculated values ( D , E ) close to the experimental ones, while keeping b 2 1 close to zero. This procedure yields good matching of the calculated ZFSPs and the experimental ones, and enables determination of the corresponding local distortions. The present results may be useful in future studies aimed at technological applications of the Huntite-type borates with the formula RM 3 (BO 3 ) 4 . The model parameters determined here may be utilized for ZFSP calculations for Cr 3+ and Mn 2+ ions at octahedral sites in single-molecule magnets and single-chain magnets. [ABSTRACT FROM AUTHOR]

An essential ingredient for our understanding of the shell structure in nuclei is the spin-orbit coupling. The fact that, in relativistic mean field (RMF) models of nuclear structure, the large spin-orbit (SO) potential emerges naturally from the form of the the Dirac equation, is one of their most important advantages. Following recent experimental studies, we investigate the size of 2p- and 1f-splittings for the isotone chain 40Ca, 38Ar, 36S, and 34Si in the framework of various relativistic density functionals. We compare our results with those of non-relativistic models and with the corresponding experimental data. [ABSTRACT FROM AUTHOR]

Eclipsing binaries are observed to have a range of eccentricities and spin-orbit misalignments (stellar obliquities). Whether such properties are primordial or arise from post-formation dynamical interactions remains uncertain. This paper considers the scenario in which the binary is the inner component of a hierarchical triple stellar system, and derives the requirements that the tertiary companion must satisfy in order to raise the eccentricity and obliquity of the inner binary. Through numerical integrations of the secular octupole-order equations of motion of stellar triples, coupled with the spin precession of the oblate primary star due to the torque from the secondary, we obtain a simple, robust condition for producing spin-orbit misalignment in the inner binary. In order to excite appreciable obliquity, the precession rate of the stellar spin axis must be smaller than the orbital precession rate due to the tertiary companion. This yields quantitative requirements on the mass and orbit of the tertiary. We also present new analytic expressions for the maximum eccentricity and range of inclinations allowing eccentricity excitation (Lidov-Kozai window), for stellar triples with arbitrary masses and including the non-Keplerian potentials introduced by general relativity, stellar tides and rotational bulges. The results of this paper can be used to place constraints on unobserved tertiary companions in binaries that exhibit high eccentricity and/or spin-orbit misalignment, and will be helpful in guiding efforts to detect external companions around stellar binaries. As an application, we consider the eclipsing binary DI Herculis, and identify the requirements that a tertiary companion must satisfy to produce the observed spin-orbit misalignment. [ABSTRACT FROM AUTHOR]

Twelve ro-vibrational energy levels of the 85 Rb 2 b 3 Π 1 u state have been observed using the Perturbation Facilitated Infrared-Infrared Double Resonance (PFIIDR) technique for the first time.Using the new observed levels as intermediate window levels, dozens of transitions into the 85 Rb 2 2 3 Π 1 g upper state ro-vibrational levels have been recorded.Compared with the experimental data of the 85 Rb 2 2 3 Π 0 g state, the average term value difference between the observed Ω = 1 and Ω = 0 components of the 85 Rb 2 2 3 Π g state levels with the same rotational quantum number, is approximately 83.1 ± 0.3 cm - 1 . This proves that the 2 3 Π g state has a spin-orbit splitting of 83.1 ± 0.3 cm - 1 , which shows that the 2 3 Π g state tends to belong to Hund’s case (a). [ABSTRACT FROM AUTHOR]

This paper is devoted to the analysis of transition arrays of magnetic-dipole ( M 1 ) type in highly charged ions. Such transitions play a significant role in highly ionized plasmas, for instance in the tungsten plasma present in tokamak devices. Using formulas recently published and their implementation in the Flexible Atomic Code for M 1 -transition array shifts and widths, absorption and emission spectra arising from transitions inside the 3* n complex of highly-charged tungsten ions are analyzed. A comparison of magnetic-dipole transitions with electric-dipole ( E 1 ) transitions shows that, while the latter are better described by transition array formulas, M 1 absorption and emission structures reveal some insufficiency of these formulas. It is demonstrated that the detailed spectra account for significantly richer structures than those predicted by the transition array formalism. This is due to the fact that M 1 transitions may occur between levels inside the same relativistic configuration, while such inner configuration transitions are not accounted for by the currently available averaging expression. In addition, because of configuration interaction, transition processes involving more than one electron jump, such as 3 p 1/2 3 d 5/2 → 3 p 3/2 3 d 3/2 , are possible but not accounted for in the transition array formulas. These missing transitions are collected in pseudo-arrays using a post-processing method described in this paper. The relative influence of inner- and inter-configuration transitions is carefully analyzed in cases of tungsten ions with net charge around 50. The need for an additional theoretical development is emphasized. [ABSTRACT FROM AUTHOR]

We report the results of first-principles calculations based on the full-potential linearized augmented plane wave (FP-LAPW + lo) method to explore the effects of alloying under the non-conventional AlN III-V compound with bismuth. We have calculated the structural and electronic properties of the binary compounds AlN and AlBi in the zinc blend structure. We have found a good agreement between our results and the experimental and theoretical results available for that binary compounds which may be a support for the results of the ternary alloys. For the AlNBi ternary alloys, we have found a rapid reduction of the energy gap by 1.31 eV/%Bi accompanied by a strong increase in the spin-orbit splitting energy (Δ) with increasing Bi composition. We have also shown that the Δ becomes greater than the energy gap for composition of Bi about 4.2% (Δ > E ). This result is significant due to the possibility of suppressing Auger recombination, which is expected to improve the high temperature performance and thermal stability of light emitting devices. Finally, we have calculated the variation of the optical properties of AlNBi compounds, such as dielectric function and refractive index versus Bi composition. [ABSTRACT FROM AUTHOR]

The control of nonlocal entanglement in solid state systems is a crucial ingredient of quantum technologies. We investigate a Cooper-pair splitter based on a double quantum dot realized in a semiconducting nanowire. In the presence of interdot tunneling the system provides a simple mechanism to develop spatial entanglement even in absence of nonlocal coupling with the superconducting lead. We discuss the possibility to control the symmetry (singlet or triplet) of spatially separated, entangled electron pairs taking advantage of the spin-orbit coupling of the nanowire. We also demonstrate that the spin-orbit coupling does not impact over the entanglement purity of the nonlocal state generated in the double quantum dot system. Cooper-pair splitter realized in a nanowire acting as double quantum dot which is coupled to one superconductor (S) and two normal leads (N). Electron singlets in the superconductor are split nonlocally into the different dots as schematically shown in the figure. The entangled electrons in the two quantum dots are then transferred by tunneling, with rate [ABSTRACT FROM AUTHOR]

Abstract In the framework of effective-mass envelope function theory, including the effect of Rashba spin-orbit coupling, the binding energyE b and spin-orbit split energy Г of the ground state of a hydrogenic donor impurity in AlGaN/GaN triangle-shaped potential heterointerface are calculated. We find that with the electric field of the heterojunction increasing, (1) the effective width of quantum well decreases and (2) the binding energy increases monotonously, and in the mean time, (3) the spin-orbit split energy Г decreases drastically. (4) The maximum of Г is 1.22 meV when the electric field of heterointerface is 1 MV/cm.

We have developed a 10- and 14-band anticrossing (BAC) models to investigate the band structures of dilute nitrides and dilute bismides alloys. In fact, the addition of Bi or N to III-V semiconductors causes a significant reduction in the band gap energy and an enhancement of the spin-orbit splitting energy. Further, the conduction and valence offsets between III-V-N/III-V-Bi were also investigated for different nitrogen and bismuth concentrations. For III-V-N/III-V-Bi heterojunctions, the strain-balanced criteria were undertaken by the zero stress analysis. The band alignment of strain-balanced GaAsN/GaAsBi, InPN/InPBi and InAsN/InAsBi is a type II. For InSbN/InSbBi heterostructure, the band lineup can be type I or II. [ABSTRACT FROM AUTHOR]

To reveal the surface elemental composition and chemical states of the Ce1 − xEu xCrO3 nano-powders (x= 0.0, 0.3, 0.5, 0.7, 0.8, 1.0), X-ray photoelectron spectroscopy was carried out in two conditions of before and after surface cleaning. This surface characterization described the core level binding energies of cerium, europium and chromium with different oxidation states. These results verified the morphology of the particles' surface which can be a confirmation of the spin disorder in these core-shell structures. The effect of surface Ar sputtering on the oxidation states were studied. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A quasi-restricted orbital (QRO) approach for the calculation of the spin-orbit term of zero-field splitting tensors (DSO tensors) by means of density functional theory (DFT) importantly features in the fact that it is free from spin contamination problems because it uses spin eigenfunctions for the zeroth order wave functions. In 2011, however, Schmitt and co-workers pointed out that in the originally proposed QRO working equation some possible excitations were not included in their sum-over-states procedure, which causes spurious DSO contributions from closed-shell subsystems located far from the magnetic molecule under study. We have revisited the derivation of the QRO working equation and modified it, making it include all possible types of excitations in the sum-over-states procedure. We have found that the spurious DSO contribution can be eliminated by taking into account contributions from all possible types of singly excited configuration state functions. We have also found that only the SOMO(α) → SOMO(β) excited configurations have nonzero contributions to the DSO tensors as long as α and β spin orbitals have the same spatial distributions and orbital energies. For the DSO tensor calculations, by using a ground state wave function free from spin contamination, we propose a natural orbital-based Pederson-Khanna (NOB-PK) method, which utilizes the single determinant wave function consisting of natural orbitals in conjunction with the Pederson-Khanna (PK) type perturbation treatment. Some relevant calculations revealed that the NOB-PK method can afford more accurate DSO tensors than the conventional PK method as well as the QRO approach in MnII complexes and ReIV-based single molecule magnets. [ABSTRACT FROM AUTHOR]

Results of microscopic and semiphenomenological calculations of features of spherical nuclei lying near the stability line and far from it are presented. The reason why the nuclei being considered are spherical is that they are magic at least in one nucleon sort. The present analysis is performed for Z = 50 and Z = 28 isotopes and for N = 50 isotones, the region extending from neutron-rich to neutron-deficient nuclei being covered. The isotopic dependence of the mean-field spin-orbit nuclear potential is revealed; systematics of energies of levels and probabilities for electromagnetic transitions is examined; and root-mean-square radii of nuclei are calculated, along with the proton- and neutron-density distributions in them. Nuclei in the vicinity of closed shells are considered in detail, and the axial-vector weak coupling constant in nuclei is evaluated. A systematic comparison of the results of calculations with experimental data is performed. [ABSTRACT FROM AUTHOR]

Coinage metal diatomic molecules are building blocks for nanostructured materials, electronic devices, and catalytically or photochemically active systems that are currently receiving lively interest in both fundamental and applied research. The theoretical study presented here elucidates the electronic structure in the ground and several low-lying excited states of the diatomic molecule CuAu that result from the combination of the atoms in their ground states nd10(n + 1)s1 2S and lowest excited d-hole states nd9(n + 1)s2 2D (n = 3 for Cu, n = 5 for Au). Full and smooth potential energy curves, obtained at the multireference configuration interaction (MRCI) level of theory, are presented for the complete set of the thus resulting 44 Λ-S terms and 86 Ω terms. Our approach is based on a scalar relativistic description using the Douglas-Kroll-Hess (DKH) Hamiltonian, with subsequent perturbative inclusion of spin-orbit (SO) coupling via the spin-orbit terms of the Breit-Pauli (BP) Hamiltonian. The Ω terms span an energy interval of about 7 eV at the ground state's equilibrium distance. Spectroscopic constants, calculated for all terms, are shown to accurately reproduce the observation for those nine terms that are experimentally known. [ABSTRACT FROM AUTHOR]

Syperheavy chemical elements 113 - 118 are 7p-elements and are members of groups 13 - 18 of the Periodic Table. Their properties depend on, in significant extent, of relativistic effects: direct, indirect and spin-orbit splitting. These effects permit to be predicted that chemical properties of the elements will differ significantly than the properties of the lighter members of the groups. It is difficult to carry out real experiments because of the short-lived isotopes of the elements. However some experiments have been realized and the results confirm the predicted properties. The hypothesis for existing of “island of stability” centered at element 114 (Flerovium) has not been confirmed. Instead, there is a region of superheavy nuclei with enhanced stability. [ABSTRACT FROM AUTHOR]

In this contribution, we describe fundamental electronic structures and spin–charge–orbital orderings of 5 d transition-metal compounds. By reviewing photoemission spectroscopy studies on CuIr 2 S 4 , IrTe 2 , Cs 2 Au 2 Br 6 , and AuTe 2 , we discuss the difference between the t 2 g and e g systems with respect to the spin–orbit splitting versus the Jahn–Teller splitting. In contrast to the Ir oxides with Mott-Hubbard character, the smallness of the charge-transfer energy plays essential roles in the exotic spin–charge–orbital orderings of the Ir and Au chalcogenides and halides. In particular, the Te 5 p hole provides an interesting interplay between the charge–orbital order and the spin–orbit interaction in IrTe 2 . [ABSTRACT FROM AUTHOR]

We study Hall and Nernst transports in monolayer MoS2 based on Green's function formalism. We have derived analytical results for spin and valley Hall conductivities in the zero temperature and spin and valley Nernst conductivities in the low temperature. We found that tuning of the band gap and spin-orbit splitting can drive system transition from spin Hall insulator (SHI) to valley Hall insulator (VHI). When the system is subjected to a temperature gradient, the spin and valley Nernst conductivities are dependent on Berry curvature. [ABSTRACT FROM AUTHOR]

We study Hall and Nernst transports in monolayer MoS2 based on Green's function formalism. We have derived analytical results for spin and valley Hall conductivities in the zero temperature and spin and valley Nernst conductivities in the low temperature. We found that tuning of the band gap and spin-orbit splitting can drive system transition from spin Hall insulator (SHI) to valley Hall insulator (VHI). When the system is subjected to a temperature gradient, the spin and valley Nernst conductivities are dependent on Berry curvature. [ABSTRACT FROM AUTHOR]