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<jats:p>In cluster science, it is challenging to identify the ground state structures (GSS) of gold (Au) clusters. Among different search approaches, first-principles method based on density functional theory (DFT) is the most reliable one with high precision. However, as the cluster size increases, it requires more expensive computational cost and becomes impracticable. In this paper, we have developed an artificial neural network (ANN) potential for Au clusters, which is trained to the DFT binding energies and forces of 9000 Au<jats:sub> <jats:italic>N</jats:italic> </jats:sub> clusters (11 ≤ <jats:italic>N</jats:italic> ≤ 100). The root mean square errors of energy and force are 13.4 meV/atom and 0.4 eV/Å, respectively. We demonstrate that the ANN potential has the capacity to differentiate the energy level of Au clusters and their isomers and highlight the need to further improve the accuracy. Given its excellent transferability, we emphasis that ANN potential is a promising tool to breakthrough computational bottleneck of DFT method and effectively accelerate the pre-screening of Au clusters’ GSS.</jats:p>

<jats:p>The magneto–mechanical coupling effect and magnetic anisotropy of Fe<jats:sub>10</jats:sub>Co<jats:sub>90</jats:sub> (FeCo) films deposited on silicon wafer (Si), flexible polyethylene terephthalate (PET), freestanding polydimethylsiloxane (PDMS), and pre-stretched 20% PDMS substrates were studied in detail. The loop squareness ratio <jats:italic>M</jats:italic> <jats:sub>r</jats:sub>/<jats:italic>M</jats:italic> <jats:sub>s</jats:sub> and the coercive <jats:italic>H</jats:italic> <jats:sub>c</jats:sub> of the FeCo film grown on a PET substrate can be obviously tuned by applying a small tensile-bending strain, and those of the FeCo film grown on a freestanding PDMS substrate can only be slightly changed when applying a relatively large tensile bending strain. For the FeCo film prepared on a 20% pre-stretched PDMS, a wrinkled morphology is obtained after removing the pre-strain. The wrinkled FeCo film can keep the magnetic properties unchanged when applying a relatively large tensile bending strain perpendicular to the wrinkles. This reveals that PDMS is an ideal substrate for magnetic films to realize flexible immutability. Our results may help for developing flexible magnetic devices.</jats:p>

<jats:p>We report the hydrothermal growth of pure and doped TiO<jats:sub>2</jats:sub> nanoparticles with different concentrations of carbon. The microstructure of the as-synthesized samples is characterized by x-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive x-ray spectroscopy (EDX), and Raman spectroscopy to understand the structure and composition. The XRD patterns confirm the formation of anatase phase of TiO<jats:sub>2</jats:sub> with the average crystallite size is calculated to be in the range of 13 nm to 14.7 nm. The functional groups of these nanostructures are characterized by Fourier transformed infrared (FT-IR) spectroscopy, which further confirms the single anatase phase of the synthesized nanostructures. UV-visible absorption spectroscopy is used to understand the absorption behavior, which shows modification in the optical bandgap from 3.13 eV (pure TiO<jats:sub>2</jats:sub>) to 3.74 eV (1.2 mol% C-doped TiO<jats:sub>2</jats:sub>). Furthermore, the Ti<jats:sup>3+</jats:sup> centers associated with oxygen vacancies are identified using electron paramagnetic resonance spectroscopy (EPR).</jats:p>

<jats:p>Complex magnetically insulated transmission line oscillator (MILO), as an important development direction, can enhance the power efficiency and generate dual-band high power microwaves (HPMs). A complex MILO and a preliminary dual-band radiation system have been proposed in our previous studies. However, the axial length of the dual-band radiation system is too long to meet the compact requirements. In this paper, a compact dual-band radiation system is presented and investigated numerically. The compact dual-band radiation system comprises a dual-band cross-shaped mode converter and a dual-band coaxial conical horn antenna. It can convert two coaxial TEM mode microwaves (1.717 GHz and 4.167 GHz) generated by the complex MILO into the coaxial TE<jats:sub>11</jats:sub> mode microwaves, and then radiate them into the air. At 1.717 GHz, the gain of the antenna is 17.9 dB, and the total return loss and diffraction loss are 1.50% and 0, respectively. At 4.167 GHz, the gain is 19.4 dB, and the total return loss and diffraction loss are 1.17% and 0.78%, respectively. The power handling capacity of the antenna is 5.1 GW at 1.717 GHz and 2.0 GW at 4.167 GHz. Comparing with the original structure, the length of the dual-band radiation system is reduced by 45.2%.</jats:p>

<jats:p>We report the electrical transport properties of InSe flakes electrostatically gated by a solid ion conductor. The large tuning capability of the solid ion conductor as gating dielectric is confirmed by the saturation gate voltage as low as ∼1 V and steep subthreshold swing (83 mV/dec). The p-type conduction behavior of InSe is obtained when negative gate voltages are biased. Chemical doping of the solid ion conductor is suppressed by inserting a buffer layer of hexagonal boron nitride (h-BN) between InSe and the solid-ion-conductor substrate. By comparing the performance of devices with and without h-BN, the capacitance of solid ion conductors is extracted to be the same as that of ∼2 nm h-BN, and the mobility of InSe on solid ion conductors is comparable to that on the SiO<jats:sub>2</jats:sub> substrate. Our results show that solid ion conductors provide a facile and powerful method for electrostatic doping.</jats:p>

<jats:p>The decentralized fuzzy inference method (DFIM) is employed as an optimization technique to reconstruct time- and space-dependent heat flux of two-dimensional (2D) participating medium. The forward coupled radiative and conductive heat transfer problem is solved by a combination of finite volume method and discrete ordinate method. The reconstruction task is formulated as an inverse problem, and the DFIM is used to reconstruct the unknown heat flux. No prior information on the heat flux distribution is required for the inverse analysis. All retrieval results illustrate that the time- and space-dependent heat flux of participating medium can be exactly recovered by the DFIM. The present method is proved to be more efficient and accurate than other optimization techniques. The effects of heat flux form, initial guess, medium property, and measurement error on reconstruction results are investigated. Simulated results indicate that the DFIM is robust to reconstruct different kinds of heat fluxes even with noisy data.</jats:p>

<jats:p>We investigate the local quantum uncertainty (LQU ) in weak measurement. An expression of weak LQU is explicitly determined. Also, we consider some cases of three special <jats:italic>X</jats:italic> states, Werner state, circulant two-qubit states, and Heisenberg model via LQU in normal and weak measurements. We find that the LQU in weak measurement is weaker than the case of strong measurement.</jats:p>

<jats:p>We analytically and numerically investigate the dynamical properties of the tilted dispersion relativistic quasiparticles emerged in a cold atomic optical lattice system. By introducing the next nearest neighboring (NNN) hopping term into Su–Schrieffer–Heeger (SSH) model, the Dirac quasiparticles with tilted dispersion relation are realized. The results show that the tilted dispersion causes a drift in relativistic quasiparticles rather than affecting interference behavior between inner states. To be specific, the relativistic phenomena of the quasiparticles induced by the inner state interference (such as <jats:italic>Zitterbewegung</jats:italic>, Klein paradox, etc.) is completely unaffected by the tilted dispersion. In order to distinguish the drift induced by tilted dispersion and common initial velocity, we calculate the momentum distribution of the relativistic quasiparticles. We obtain the difference between the drift induced by initial velocity and tilted dispersion. The former affects the ZB, while the latter does not. By using this character, we propose a quench dynamics scheme to obtain a stable mono-spin state. The proposed cold atomic lattice system would provide a promising platform in exploring the intrinsic exotic physics of relativistic quasiparticles and the related systems.</jats:p>