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<jats:p> <jats:italic>The electronic structures of Ti<jats:sub>2</jats:sub>NbSb with Hg<jats:sub>2</jats:sub>CuTi structure and TiZrNbSb with LiMgPdSn structure are investigated using first-principles calculations. The results indicate that Ti<jats:sub>2</jats:sub>NbSb is a fully compensated ferrimagnetic spin-gapless semiconductor with an energy gap of 0.13 eV, and TiZrNbSb is a half-metallic fully compensated ferrimagnet with a half-metallic gap of 0.17 eV. For Ti<jats:sub>2</jats:sub>NbSb, the total energy of the Hg<jats:sub>2</jats:sub>CuTi structure is 0.62 eV/f.u. higher than that of the L2<jats:sub>1</jats:sub> structure, which is the ground state, and for TiZrNbSb, the total energy of the structure considered in this work is only 0.15 eV/f.u. larger than that of the ground state. Thus both of them may be good candidates for spintronic applications</jats:italic>.</jats:p>

<jats:p> <jats:italic>We report Shubnikov–de Haas (SdH) oscillations of a three-dimensional (3D) Dirac semimetal candidate of layered material ZrTe<jats:sub>5</jats:sub> single crystals through contactless electron spin resonance (ESR) measurements with the magnetic field up to 1.4 T. The ESR signals manifest remarkably anisotropic characteristics with respect to the direction of the magnetic field, indicating an anisotropic Fermi surface in ZrTe<jats:sub>5</jats:sub>. Further experiments demonstrate that the ZrTe<jats:sub>5</jats:sub> single crystals have the signature of massless Dirac fermions with nontrivial <jats:italic>π</jats:italic> Berry phase, key evidence for 3D Dirac/Weyl fermions. Moreover, the onset of quantum oscillation of our ZrTe<jats:sub>5</jats:sub> crystals revealed by the ESR can be derived down to 0.2 T, much smaller than the onset of SdH oscillation determined by conventional magnetoresistance measurements. Therefore, ESR measurement is a powerful tool to study the topologically nontrivial electronic structure in Dirac/Weyl semimetals and other topological materials with low bulk carrier density</jats:italic>.</jats:p>

<jats:p> <jats:italic>We present a quantum study on the electrical behavior of the self-switching diode (SSD). Our simulation is based on non-equilibrium Green’s function formalism along with an atomistic tight-binding model. Using this method, electrical characteristics of devices, such as turn-on voltage, rectification ratio, and differential resistance, are investigated. Also, the effects of geometrical variations on the electrical parameters of SSDs are simulated. The carrier distribution inside the nano-channel is successfully simulated in a two-dimensional model under zero, reverse, and forward bias conditions. The results indicate that the turn-on voltage, rectification ratio, and differential resistance can be optimized by choosing appropriate geometrical parameters</jats:italic>.</jats:p>

<jats:p> <jats:italic>This work details a study based on HfS<jats:sub>2</jats:sub> transistors utilizing an n-octadecylphosphonic acid-based self-assembled monolayer (SAM) as the gate dielectric. The fabrication of the SAM-based two-dimensional (2D) material transistor is simple and can be used to improve the quality of the interface of air-sensitive 2D materials. In comparison to HfS<jats:sub>2</jats:sub> transistors utilizing a conventional Al<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> gate insulator by atomic layer deposition, HfS<jats:sub>2</jats:sub> transistors utilizing an SAM as the gate dielectric can reduce the operation region from 4V to 2V, enhance the field-effect mobility from 0.03 cm<jats:sup>2</jats:sup>/Vs to 0.75 cm<jats:sup>2</jats:sup>/Vs, improve the sub-threshold swing from 404 mV/dec to 156 mV/dec, and optimize the hysteresis to 0.03 V, thus demonstrating improved quality of the semiconductor/insulator interface</jats:italic>.</jats:p>

<jats:p> <jats:italic>We report the temperature, magnetic field and time dependences of magnetization in advanced Ba122 superconducting tapes. The sample exhibits peculiar vortex creep behavior. Below 10 K, the normalized magnetization relaxation rate S = dln(−M)/dln(t) shows a temperature-insensitive plateau with a value comparable to that of low-temperature superconductors, which can be explained within the framework of collective creep theory. It then enters into a second collective creep regime when the temperature increases. Interestingly, the relaxation rate below 20K tends to reach saturation with increasing the field. However, it changes to a power law dependence on the field at a higher temperature. A vortex phase diagram composed of the collective and the plastic creep regions is shown. Benefiting from the strong grain boundary pinning, the advanced Ba122 superconducting tape has potential to be applied not only in liquid helium but also in liquid hydrogen or at temperatures accessible with cryocoolers</jats:italic>.</jats:p>

<jats:p> <jats:italic>High resolution laser-based angle-resolved photoemission measurements are carried out on an overdoped superconductor Bi</jats:italic> <jats:sub>2</jats:sub> <jats:italic>Sr</jats:italic> <jats:sub>2</jats:sub> <jats:italic>CaCu</jats:italic> <jats:sub>2</jats:sub> <jats:italic>O</jats:italic> <jats:sub>8+<jats:italic>δ</jats:italic> </jats:sub> <jats:italic>with a T</jats:italic> <jats:sub>c</jats:sub> <jats:italic>of 75 K. Two Fermi surface sheets caused by bilayer splitting are clearly identified with rather different doping levels: the bonding sheet corresponds to a doping level of 0.14, which is slightly underdoped while the antibonding sheet has a doping of 0.27 that is heavily overdoped, giving an overall doping level of 0.20 for the sample. Different superconducting gap sizes on the two Fermi surface sheets are revealed. The superconducting gap on the antibonding Fermi surface sheet follows a standard d-wave form while it deviates from the standard d-wave form for the bonding Fermi surface sheet. The maximum gap difference between the two Fermi surface sheets near the antinodal region is ∼2 meV. These observations provide important information for studying the relationship between the Fermi surface topology and superconductivity, and the layer-dependent superconductivity in high temperature cuprate superconductors.</jats:italic> </jats:p>

<jats:p> <jats:italic>The classical frustrated antiferromagnetic J<jats:sub>1</jats:sub>–J<jats:sub>2</jats:sub> model is considered in a description of the classical spin wave for a vector spin system. Its ground state (GS) spin ordering is analyzed by minimizing its energy. Our analytical derivations show that all the spins in the GS phase must lie in planes that are parallel to each other. When applying the derived formulations to concrete lattices such as the square and simple cubic lattices, we find that in the large J<jats:sub>2</jats:sub> region, a large continuous GS degeneracy concluded by a qualitative analysis is lifted, and collinear striped ordering is selected as the GS phase</jats:italic>.</jats:p>

<jats:p> <jats:italic>Off-stoichiometric full-Heusler alloy Co<jats:sub>2</jats:sub>MnAl thin films with different thicknesses are epitaxially grown on GaAs (001) substrates by molecular-beam epitaxy. The composition of the films, close to Co<jats:sub>1.65</jats:sub>Mn<jats:sub>1.35</jats:sub>Al (CMA), is determined by x-ray photoelectron spectroscopy and energy dispersive spectroscopy. Tunable perpendicular magnetic anisotropy (PMA) from 3.41 Merg/cm<jats:sup>3</jats:sup> to 1.88 Merg/cm<jats:sup>3</jats:sup> with the thickness increasing from 10 nm to 30 nm is found, attributed to the relaxation of residual compressive strain. Moreover, comparing with the ultrathin CoFeB/MgO used in the conventional perpendicular magnetic tunnel junction, the CMA electrode has a higher magnetic thermal stability with more volume involved. The PMA in CMA films is sustainable up to 300°C, compatible with semiconductor techniques. This work provides a possibility for the development of perpendicular magnetized full-Heusler compounds with high thermal stability and spin polarization</jats:italic>.</jats:p>

<jats:p> <jats:italic>It has been demonstrated that the zigzag honeycomb nanoribbons exhibit an intriguing edge magnetism. Here the effect of the anisotropy on the edge magnetism in zigzag honeycomb nanoribbons is investigated using two kinds of large-scale quantum Monte Carlo simulations. The anisotropy in zigzag honeycomb nanoribbons is characterized by the ratios of nearest-neighbor hopping integrals t<jats:sub>1</jats:sub> in one direction and t<jats:sub>2</jats:sub> in another direction. Considering the electron-electron correlation, it is shown that the edge ferromagnetism could be enhanced greatly as t<jats:sub>2</jats:sub>/|t<jats:sub>1</jats:sub>| increases from 1 to 3, which not only presents an avenue for the control of this magnetism but is also useful for exploring further novel magnetism in new nano-scale materials</jats:italic>.</jats:p>

<jats:p> <jats:italic>Magnetization reversal in magnetic soft/hard bilayer systems is studied analytically by means of a variational method for magnetic energies in a continuum model. The demagnetization curve is involved with nonlinear equations, and the solution is given implicitly in the form of Jacobi functions, which is valid for the total reversal process. Based on the non-trivial solutions, hysteresis loops, as well as the maximum energy product (BH)<jats:sub>max</jats:sub> versus thicknesses of soft/hard layers are obtained. With regard to (BH)<jats:sub>max</jats:sub>, improvement of the remanence competes with loss of coercive force. As a result, an optimum condition exists. For a given thickness of the hard layer, the optimum condition at which the largest (BH)<jats:sub>max</jats:sub> could be achieved is discussed, which is slightly different from previous works</jats:italic>.</jats:p>