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<jats:p>A novel super-junction LDMOS with low resistance channel (LRC), named LRC-LDMOS based on the silicon-on-insulator (SOI) technology is proposed. The LRC is highly doped on the surface of the drift region, which can significantly reduce the specific on resistance (<jats:italic>R</jats:italic> <jats:sub>on,sp</jats:sub>) in forward conduction. The charge compensation between the LRC, N-pillar, and P-pillar of the super-junction are adjusted to satisfy the charge balance, which can completely deplete the whole drift, thus the breakdown voltage (<jats:italic>BV</jats:italic>) is enhanced in reverse blocking. The three-dimensional (3D) simulation results show that the <jats:italic>BV</jats:italic> and <jats:italic>R</jats:italic> <jats:sub>on,sp</jats:sub> of the device can reach 253 V and 15.5 mΩ ⋅ cm<jats:sup>2</jats:sup>, respectively, and the Baliga’s figure of merit (<jats:italic>FOM</jats:italic> = <jats:italic>BV</jats:italic> <jats:sup>2</jats:sup>/<jats:italic>R</jats:italic> <jats:sub>on,sp</jats:sub>) of 4.1 MW/cm<jats:sup>2</jats:sup> is achieved, breaking through the silicon limit.</jats:p>

<jats:p>Low dimensional materials are suitable candidates applying in next-generation high-performance electronic, optoelectronic, and energy storage devices because of their uniquely physical and chemical properties. In particular, one-dimensional (1D) atomic wires (AWs) exfoliating from 1D van der Waals (vdW) bulks are more promising in next generation nanometer (nm) even sub-nm device applications owing to their width of few-atoms scale and free dandling bonds states. Although several 1D AWs have been experimentally prepared, few 1D AW candidates could be practically applied in devices owing to lack of enough suitable 1D AWs. Herein, 367 kinds of 1D AWs have been screened and the corresponding computational database including structures, electronic structures, magnetic states, and stabilities of these 1D AWs has been organized and established. Among these systems, unary and binary 1D AWs with relatively small exfoliation energy are thermodynamically stable and theoretically feasible to be exfoliated. More significantly, rich quantum states emerge, such as 1D semiconductors, 1D metals, 1D semimetals, and 1D magnetism. This database will offer an ideal platform to further explore exotic quantum states and exploit practical device applications using 1D materials. The database are openly available at http://www.dx.doi.org/10.11922/sciencedb.j00113.00004.</jats:p>

<jats:p>Dichloro [1,2-bis (diphenylphosphino) ethane] nickel<jats:sup>2+</jats:sup> (NiCl<jats:sub>2</jats:sub>(dppe)) is an organic compound containing C<jats:sub>26</jats:sub>H<jats:sub>24</jats:sub>P<jats:sub>2</jats:sub>(dppe) molecules and Cl<jats:sup>−</jats:sup>, Ni<jats:sup>2+</jats:sup> ions. The large-size NiCl<jats:sub>2</jats:sub>(dppe) single crystals with longest dimension of 4 mm were grown by the method of slow evaporation of organic solution. Single crystal x-ray diffraction spectrum indicates that the single crystal is of high quality. Magnetization results of the NiCl<jats:sub>2</jats:sub>(dppe) single crystals show an anisotropic paramagnetism behavior and diamagnetic background, which come from Ni<jats:sup>2+</jats:sup> ions and benzene ring, respectively. However, according to the specific heat results with temperature down to 0.1 K and magnetic field up to 14 T, no expected field-induced quantum phase transition was observed in NiCl<jats:sub>2</jats:sub>(dppe) single crystals.</jats:p>

<jats:p>The paper aims at modeling and simulating the atomization process of the close-coupled ring-hole nozzle in vacuum induction gas atomization (VIGA) for metallic powder production. First of all, the primary atomization of the ring-hole nozzle is simulated by the volume of fluid (VOF) coupled large eddy simulation (LES) model. To simulate the secondary atomization process, we use the method of selecting the droplet sub-model and the VOF model. The results show that the ring-hole nozzle forms a gas recirculation zone at the bottom of the delivery tube, which is the main reason for the formation of an annular liquid film during the primary atomization. In addition, the primary atomization process of the ring-hole nozzle consists of three stages: the formation of the serrated liquid film tip, the appearance and shedding of the ligaments, and the fragmentation of ligaments. At the same time, the primary atomization mainly forms spherical droplets and long droplets, but only the long droplets can be reserved and proceed to the secondary atomization. Moreover, increasing the number of ring holes from 18 to 30, the mass median diameter (MMD, <jats:italic>d</jats:italic> <jats:sub>50</jats:sub>) of the primary atomized droplets decreases first and then increases, which is mainly due to the change of the thickness of the melt film. Moreover, the secondary atomization of the ring-hole nozzles is mainly in bag breakup mode and multimode breakup model, and bag breakup will result in the formation of hollow powder, which can be avoided by increasing the gas velocity.</jats:p>

<jats:p>We used the Jordan–Wigner transform and the invariant eigenoperator method to study the magnetic phase diagram and the magnetization curve of the spin-1/2 alternating ferrimagnetic diamond chain in an external magnetic field at finite temperature. The magnetization versus external magnetic field curve exhibits a 1/3 magnetization plateau at absolute zero and finite temperatures, and the width of the 1/3 magnetization plateau was modulated by tuning the temperature and the exchange interactions. Three critical magnetic field intensities <jats:italic>H</jats:italic> <jats:sub>CB</jats:sub>, <jats:italic>H</jats:italic> <jats:sub>CE</jats:sub> and <jats:italic>H</jats:italic> <jats:sub>CS</jats:sub> were obtained, in which the <jats:italic>H</jats:italic> <jats:sub>CB</jats:sub> and <jats:italic>H</jats:italic> <jats:sub>CE</jats:sub> correspond to the appearance and disappearance of the 1/3 magnetization plateau, respectively, and the higher <jats:italic>H</jats:italic> <jats:sub>CS</jats:sub> correspond to the appearance of fully polarized magnetization plateau of the system. The energies of elementary excitation <jats:italic>ℏ ω</jats:italic> <jats:sub> <jats:italic>σ</jats:italic>,<jats:italic>k</jats:italic> </jats:sub> (<jats:italic>σ</jats:italic> = 1, 2, 3) present the extrema of zero at the three critical magnetic fields at 0 K, i.e., [<jats:italic>ℏ ω</jats:italic> <jats:sub>3,<jats:italic>k</jats:italic> </jats:sub>(<jats:italic>H</jats:italic> <jats:sub>CB</jats:sub>)]<jats:sub>min</jats:sub> = 0, [<jats:italic>ℏ ω</jats:italic> <jats:sub>2,<jats:italic>k</jats:italic> </jats:sub>(<jats:italic>H</jats:italic> <jats:sub>CE</jats:sub>)]<jats:sub>max</jats:sub> = 0 and [<jats:italic>ℏ ω</jats:italic> <jats:sub>2,<jats:italic>k</jats:italic> </jats:sub>(<jats:italic>H</jats:italic> <jats:sub>CS</jats:sub>)]<jats:sub>min</jats:sub> = 0, and the magnetic phase diagram of magnetic field versus different exchange interactions at 0 K was established by the above relationships. According to the relationships between the system’s magnetization curve at finite temperatures and the critical magnetic field intensities, the magnetic field-temperature phase diagram was drawn. It was observed that if the magnetic phase diagram shows a three-phase critical point, which is intersected by the ferrimagnetic phase, the ferrimagnetic plateau phase, and the Luttinger liquid phase, the disappearance of the 1/3 magnetization plateau would inevitably occur. However, the 1/3 magnetization plateau would not disappear without the three-phase critical point. The appearance of the 1/3 magnetization plateau in the low temperature region is the macroscopic manifestations of quantum effect.</jats:p>

<jats:p>The in-plane effective 90° magnetization rotation of Co<jats:sub>2</jats:sub>FeAl thin film grown on PMN-PT substrate induced by the electric field is investigated at room temperature. The magnetic hysteresis loops under different positive and negative electric fields are obtained, which reveals remanent magnetization can be mediated by the electric field. Moreover, under positive electric fields, the obvious 90° magnetization rotation can be observed, while remanent magnetization is nearly unchanged under negative electric fields. The result is consistent with the electric field dependence of effective magnetic field, which can be attributed to the piezostrain effect in Co<jats:sub>2</jats:sub>FeAl/PMN-PT structure. In addition, the piezostrain-mediated 90° magnetization rotation can be demonstrated by the result of resonance field changing with electric field in the measurement of ferromagnetic resonance, which is promising for the design of future multiferroic devices.</jats:p>

<jats:p>We present detailed investigations of structural and static/dynamic magnetic properties of hydrogenated hcp-Co<jats:sub>80</jats:sub> <jats:sup>57</jats:sup>Fe<jats:sub>4</jats:sub>Ir<jats:sub>16</jats:sub> soft magnetic thin films. Two different kinds of defects, <jats:italic>i.e.</jats:italic>, destructive and non-destructive, were demonstrated by controlling the negative bias voltage of the hydrogenation process. Our results show that the structure and magnetic properties of our sample can be tuned by the density of the induced defects. These results provide better understanding of the hydrogenation effect and thus can be used in the future for materials processing to meet the requirements of different devices.</jats:p>

<jats:p>Transition metal dichalcogenides (TMDs), being valley selectively, are an ideal system hosting excitons. Stacking TMDs together to form heterostructure offers an exciting platform to engineer new optical and electronic properties in solid-state systems. However, due to the limited accuracy and repetitiveness of sample preparation, the effects of interlayer coupling on the electronic and excitonic properties have not been systematically investigated. In this report, we study the photoluminescence spectra of bilayer-bilayer MoS<jats:sub>2</jats:sub>/WS<jats:sub>2</jats:sub> heterostructure with a type II band alignment. We demonstrate that thermal annealing can increase interlayer coupling in the van der Waals heterostructures, and after thermally induced band hybridization such heterostructure behaves more like an artificial new solid, rather than just the combination of two individual TMD components. We also carry out experimental and theoretical studies of the electric controllable direct and indirect infrared interlayer excitons in such system. Our study reveals the impact of interlayer coupling on interlayer excitons and will shed light on the understanding and engineering of layer-controlled spin-valley configuration in twisted van der Waals heterostructures.</jats:p>

<jats:p>The realization of active modulation of reflection phase based on metasurfaces is of great significance for flexible control of electromagnetic wavefront, which makes metasurfaces have practical application values in polarization conversion, beam steering, metalens, etc. In this paper, a reflection phase tunable gap-surface plasmon (GSP) metasurface based on phase change materials Ge<jats:sub>2</jats:sub>Sb<jats:sub>2</jats:sub>Te<jats:sub>5</jats:sub> (GST) is designed and experimentally demonstrated. By virtue of the characteristics of large permittivities difference before and after GST phase transition and the existence of stable intermediate states, the continuous modulation of near-infrared reflection phase larger than 200° has been realized. At the same time, through the reasonable design of the structure sizes, the reflection has been maintained at about 0.4 and basically does not change with the GST phase transition, which improved the working efficiency of the metasurface significantly. In addition, the coupled-mode theory (CMT) is introduced to make a full analysis of the modulation mechanism of the reflection phase, which proves that the phase transition of GST can induce the transition of metasurface working state from overcoupling mode to critical coupling mode. The improvement of the metasurface working efficiency has practical values for wavefront modulation.</jats:p>

<jats:p>Due to their excellent carrier mobility, high absorption coefficient and narrow bandgap, most 2D IVA metal chalcogenide semiconductors (GIVMCs, metal = Ge, Sn, Pb; chalcogen = S, Se) are regarded as promising candidates for realizing high-performance photodetectors. We synthesized high-quality two-dimensional (2D) tin sulfide (SnS) nanosheets using the physical vapor deposition (PVD) method and fabricated a 2D SnS visible-light photodetector. The photodetector exhibits a high photoresponsivity of 161 A⋅W<jats:sup>−1</jats:sup> and possesses an external quantum efficiency of 4.45 × 10<jats:sup>4</jats:sup>%, as well as a detectivity of 1.15 × 10<jats:sup>9</jats:sup> Jones under 450 nm blue light illumination. Moreover, under poor illumination at optical densities down to 2 mW⋅cm<jats:sup>−2</jats:sup>, the responsivity of the device is higher than that at stronger optical densities. We suggest that a photogating effect in the 2D SnS photodetector is mainly responsible for its low-light responsivity. Defects and impurities in 2D SnS can trap carriers and form localized electric fields, which can delay the recombination process of electron-hole pairs, prolong carrier lifetimes, and thus improve the low-light responsivity. This work provides design strategies for detecting low levels of light using photodetectors made of 2D materials.</jats:p>