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<jats:p>Unique topological states emerged in various topological insulators (TI) have been proved with great application value for robust wave regulation. In this work, we demonstrate the parity inversion related to the definition of the primitive cell in one common lattice, and realize a type of symmetry-controlled edge states confined on the zigzag interfaces of the graphene-like sonic topological crystal. By simply sliding the selected ‘layer’ near the interface, the coupling of the pseudospin states induced by the multiple scattering for the <jats:italic>C</jats:italic> <jats:sub>6<jats:italic>v</jats:italic> </jats:sub> lattice results in the adjustment of the edge states. Based on the physics of the states, we experimentally propose a prototype of acoustic topological filter hosting multiple channels with independent adjustable edge states and realize the selective high transmission. Our work diversifies the prospects for the applications of the gapped edge states in the robust wave regulation, and proposes a frame to design new topological devices.</jats:p>

<jats:p>In this work, a novel carbon allotrope <jats:italic>t</jats:italic>P40 carbon with space group <jats:italic>P</jats:italic>4/<jats:italic>mmm</jats:italic> is proposed. The structural stability, mechanical properties, elastic anisotropy, and electronic properties of <jats:italic>t</jats:italic>P40 carbon are investigated systematically by using density functional theory (DFT). The calculated elastic constants and phonon dispersion spectra indicate that the <jats:italic>t</jats:italic>P40 phase is a metastable carbon phase with mechanical stability and dynamic stability. The <jats:italic>B</jats:italic>/<jats:italic>G</jats:italic> ratio indicates that <jats:italic>t</jats:italic>P40 carbon is brittle from 0 GPa to 60 GPa, while <jats:italic>t</jats:italic>P40 carbon is ductile from 70 GPa to 100 GPa. Additionally, the anisotropic factors and the directional dependence of the Poisson’s ratio, shear modulus, and Young’s modulus of <jats:italic>t</jats:italic>P40 carbon at different pressures are estimated and plotted, suggesting that the <jats:italic>t</jats:italic>P40 carbon is elastically anisotropic. The calculated hardness values of <jats:italic>t</jats:italic>P40 carbon are 44.0 GPa and 40.2 GPa obtained by using Lyakhov–Oganov’s model and Chen’s model, respectively, which means that the <jats:italic>t</jats:italic>P40 carbon can be considered as a superhard material. The electronic band gap within Heyd–Scuseria–Ernzerhof hybrid functional (HSE06) is 4.130 eV, and it is found that the <jats:italic>t</jats:italic>P40 carbon is an indirect and wider band gap semiconductor material.</jats:p>

<jats:p>The various morphologies of tracks in MoS<jats:sub>2</jats:sub> irradiated by swift heavy ions at normal and 30° incidence with 9.5–25.0 MeV/u <jats:sup>86</jats:sup>Kr, <jats:sup>129</jats:sup>Xe, <jats:sup>181</jats:sup>Ta, and <jats:sup>209</jats:sup>Bi ions were investigated by transmission electron microscopy. The diameter of ion tracks increases from 1.9 nm to 4.5 nm with increasing electronic energy loss. The energy loss threshold of the track formation in MoS<jats:sub>2</jats:sub> is predicted as about 9.7 keV/nm based on the thermal spike model and it seems consistent with the experimental results. It is shown that the morphology of ion tracks is related to the penetration length of ions in MoS<jats:sub>2</jats:sub>. The formation process of ion tracks is discussed based on the cooperative process of outflow and recrystallization of the molten phase during rapid quenching.</jats:p>

<jats:p>Since the discoveries of polymeric nitrogen, named cg-N (2004), LP-N (2014), HLP-N (2019), another polymorph named black phosphorus nitrogen (BP-N) was synthesized at high-pressure-high-temperature conditions. The narrow existing pressure region and similar synthesized pressure of BP-N compared with cg-N indicate that the stable energy and enthalpy of formation of these two structures are close to each other, which was confirmed by our theoretical calculation. In order to obtain the pressure region of BP-N phase, pure N<jats:sub>2</jats:sub> and TiN/Pb + N<jats:sub>2</jats:sub> precursors were used for laser-heating high pressure experiments in diamond anvil cell (DAC), and the phase identity was examined by Raman and XRD mapping. BP-N can be synthesized in the pressure range of 130 GPa to 140 GPa with the assistance of heating absorber. With the decrease of the pressure, BP-N can be quenched to ∼ 40 GPa. The synthesizing pressure–temperature and the stable pressure region of BP-N are important for further exploration of BP-N and its kinetic and thermal dynamic relationship with other polymeric nitrogen, especially cg-N.</jats:p>

<jats:p>A simple two-dimensional phononic crystal hosting topologically protected edge states is proposed to emulate the quantum spin Hall effect in electronic systems, whose phononic topological phase can be reconfigured through the rotation of scatters. In particular, the band inversion occurs between two pairs of high-order compound states, resulting in topological phase transition from trivial to nontrivial over a relatively broad high-frequency range. This is further evidenced by an effective Hamiltonian derived by the <jats:italic>k</jats:italic> ⋅ <jats:italic>p</jats:italic> perturbation theory. The phononic topology is related to a pseudo-time-reversal symmetry constructed by the point group symmetry of two doubly degenerate eigenstates. Numerical simulations unambiguously demonstrate robust helical edge states whose pseudospin indices are locked to the propagation direction along the interface between topologically trivial and nontrivial phononic crystals. Our designed phononic systems provide potential applications in robust acoustic signal transport along any desired path over a high-frequency range.</jats:p>

<jats:p>Vanadium oxide films were grown by atomic layer deposition using the tetrakis[ethylmethylamino] vanadium as the vanadium precursor and H<jats:sub>2</jats:sub>O as the oxide source. The effect of the source temperature on the quality of vanadium oxide films and valence state was investigated. The crystallinity, surface morphology, film thickness, and photoelectric properties of the films were characterized by x-ray diffraction, atomic force microscope, scanning electron microscope, <jats:italic>I</jats:italic>–<jats:italic>V</jats:italic> characteristics curves, and UV–visible spectrophotometer. By varying the source temperature, the content of V<jats:sub>6</jats:sub>O<jats:sub>11</jats:sub>, VO<jats:sub>2</jats:sub>, and V<jats:sub>6</jats:sub>O<jats:sub>13</jats:sub> in the vanadium oxide film increased, that is, as the temperature increased, the average oxidation state generally decreased to a lower value, which is attributed to the rising of the vapor pressure and the change of the ionization degree for organometallics. Meanwhile, the root-mean-square roughness decreased and the metal–insulator transition temperature reduced. Our study is great significance for the fabrication of vanadium oxide films by atomic layer deposition.</jats:p>

<jats:p>The exciton dispersion is examined in the case of four selected prototypical molecular solids: pentacene, tetracene, picene, and chrysene. The model parameters are determined by fitting to experimental data obtained by inelastic electron scattering. Within the picture that relies on Frenkel-type excitons we obtain that theoretical dispersion curves along different directions in the Brillouin zone are in good agreement with the experimental data, suggesting that the influence of charge-transfer excitons on exciton dispersion of the analyzed organic solids is not as large as proposed. In reciprocal space directions where Davydov splitting is observed we employ the upgraded version of Hamiltonian used in <jats:italic>Materials</jats:italic> <jats:bold>11</jats:bold>, 2219 (2018).</jats:p>

<jats:p>Anderson localization (AL) phenomena usually exist in systems with random potential. However, disorder-free quantum many-body systems with local conservation can also exhibit AL or even many-body localization transition. We show that the AL phase exists in a modified Kondo lattice without external random potential. The density of state, inverse participation ratio and temperature-dependent resistance are computed by classical Monte Carlo simulation, which uncovers an AL phase from the previously studied Fermi liquid and Mott insulator regimes. The occurrence of AL roots from quenched disorder formed by conservative localized moments. Interestingly, a many-body wavefunction is found, which captures elements in all three paramagnetic phases and is used to compute their quantum entanglement. In light of these findings, we expect that the disorder-free AL phenomena can exist in generic translation-invariant quantum many-body systems.</jats:p>

<jats:p>Nowadays, magnetic cooling (MC) technology by using the magnetocaloric effect (MCE) has attracted extensive research interest for its promising practical applications. A constant large/giant MCE covers wide refrigeration temperatures (denote as table-like shape) is beneficial for obtaining high efficiency performance for MC. In this paper, the HoNi/HoNi<jats:sub>2</jats:sub> composite was successfully synthesized by arc-melting method and proved to be composed of HoNi and HoNi<jats:sub>2</jats:sub> crystalline phases with weight ratios of 52.4 wt.% and 47.6 wt.%, respectively. The maximum magnetic entropy change (<jats:inline-formula> <jats:tex-math><?CDATA $-{\rm{\Delta }}{S}_{M}^{{\rm{\max }}}$?></jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mo>−</mml:mo> <mml:mi mathvariant="normal">Δ</mml:mi> <mml:msubsup> <mml:mi>S</mml:mi> <mml:mi>M</mml:mi> <mml:mrow> <mml:mi mathvariant="normal">max</mml:mi> </mml:mrow> </mml:msubsup> </mml:mrow> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpb_29_10_107502_ieqn1.gif" xlink:type="simple" /> </jats:inline-formula>) is 18.23 J/(kg⋅K), and the refrigerant capacity values <jats:italic>RC</jats:italic> <jats:sub>1</jats:sub>, <jats:italic>RC</jats:italic> <jats:sub>2</jats:sub>, and <jats:italic>RC</jats:italic> <jats:sub>3</jats:sub> are 867.9 J/kg, 676.4 J/kg, and 467.8 J/kg with Δ<jats:italic>H</jats:italic> = 0–70 kOe, respectively. The table-like shape MCE and large refrigerant capacity values make the composite attractive for cryogenic MC using the Ericsson cycle.</jats:p>

<jats:p>Tuning magnetic damping constant in dedicated spintronic devices has important scientific and technological implications. Here we report on anisotropic damping in various compositional amorphous CoFeB films grown on GaAs(001) substrates. Measured by a vector network analyzer-ferromagnetic resonance (VNA-FMR) equipment, a giant magnetic damping anisotropy of 385%, i.e., the damping constant increases by about four times, is observed in a 10-nm-thick Co<jats:sub>40</jats:sub>Fe<jats:sub>40</jats:sub>B<jats:sub>20</jats:sub> film when its magnetization rotates from easy axis to hard axis, accompanied by a large and pure in-plane uniaxial magnetic anisotropy (UMA) with its anisotropic field of about 450 Oe. The distinct damping anisotropy is mainly resulted from anisotropic two-magnon-scattering induced by the interface between the ferromagnetic layer and the substrate, which also generates a significant UMA in the film plane.</jats:p>