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Studies of supercooled liquid phase‐change materials are important for the development of phase‐change memory and neuromorphic computing devices. Herein, a machine‐learning (ML)‐based interatomic potential for Ge2Sb2Te5 (GST) to conduct large‐scale molecular dynamics simulations of liquid and supercooled liquid GST is used. A pronounced effect of the thermostat parameters on the simulation results is demonstrated, and it is shown how using a Langevin thermostat with optimized damping values can lead to excellent agreement with reference ab initio molecular dynamics (AIMD) simulations. Structural and dynamical analyses are presented, including the studies of radial and angular distributions, homopolar bonds, and the temperature‐dependent diffusivity. Herein, the usefulness of ML‐driven molecular dynamics for further studies of supercooled liquid GST, with length and timescales far exceeding those that are accessible to AIMD is demonstrated. [ABSTRACT FROM AUTHOR]

Unconventional superconductivity, in particular, in noncentrosymmetric systems, has been a long-sought topic in condensed matter physics. Recently, Re-based superconductors have attracted great attention owing to the potential time-reversal symmetry breaking in their superconducting states. We report the superconducting properties of noncentrosymmetric compounds TaxRe1 – x with 0.1 ≤ x ≤ 0.25, and find that the superconducting transition temperature reaches a maximum of ∼8 K at the optimal level x = 0.15. Nevertheless, muon-spin rotation and relaxation measurements reveal no time-reversal symmetry breaking existing in its superconducting state, which is in sharp contrast to both centrosymmetric Re metal and many other noncentrosymmetric Re-based superconductors. [ABSTRACT FROM AUTHOR]

The measurements of magnetization, longitudinal and Hall resistivities are carried out on the intrinsic antiferromagnetic (AFM) topological insulator EuSn2As2. It is confirmed that our EuSn2As2crystal is a heavily hole doping A-type AFM metal with the Néel temperature TN = 24 K, with a metamagnetic transition from an AFM to a ferromagnetic (FM) phase occurring at a certain critical magnetic field for the different field orientations. Meanwhile, we also find that the carrier concentration does not change with the evolution of magnetic order, indicating that the weak interaction between the localized magnetic moments from Eu2+ 4f7orbits and the electronic states near the Fermi level. Although the quantum anomalous Hall effect (AHE) is not observed in our crystals, it is found that a relatively large negative magnetoresistance (−13%) emerges in the AFM phase, and exhibits an exponential dependence upon magnetic field, whose microscopic origin is waiting to be clarified in future research. [ABSTRACT FROM AUTHOR]

The measurements of magnetization, longitudinal and Hall resistivities are carried out on the intrinsic antiferromagnetic (AFM) topological insulator EuSn2As2. It is confirmed that our EuSn2As2crystal is a heavily hole doping A-type AFM metal with the Néel temperature TN = 24 K, with a metamagnetic transition from an AFM to a ferromagnetic (FM) phase occurring at a certain critical magnetic field for the different field orientations. Meanwhile, we also find that the carrier concentration does not change with the evolution of magnetic order, indicating that the weak interaction between the localized magnetic moments from Eu2+ 4f7orbits and the electronic states near the Fermi level. Although the quantum anomalous Hall effect (AHE) is not observed in our crystals, it is found that a relatively large negative magnetoresistance (−13%) emerges in the AFM phase, and exhibits an exponential dependence upon magnetic field, whose microscopic origin is waiting to be clarified in future research. [ABSTRACT FROM AUTHOR]

Trees are characterized with selective absorption of different forms of nitrogen. Ammonium nitrogen (NH 4 + -N) and nitrate nitrogen (NO 3 - -N) are the main forms of nitrogen for plant absorption. We examined the differences of absorption between NH 4 + -N and NO 3 - -N for 1-year-old Machilus pauhoi seedlings planted in local hilly red soil in a pot experiment. A controlled experiment with 7 different NH 4 + -N/NO 3 - -N treatments was conducted, to study the effects of nitrogen forms and different NH 4 + -N/NO 3 - -N ratios on the growth and leaf traits of M. pauhoi seedlings. The results showed that there were no significant differences in the relative growth rate of ground diameter (GD), plant height (TH), and biomass (RGR) of M. pauhoi seedlings with different NH 4 + -N/NO 3 - -N ratios for four months, but these parameters were relatively high under the treatment of NH 4 + -N:NO 3 - -N=5:5. The seedlings of M. pauhoi didn't show obvious preference for NH 4 + -N and NO 3 - -N in short term. The extremely low NH 4 + -N/NO 3 - -N ratio application was unsuitable for their growth. Different NH 4 + -N/NO 3 - -N application had significant effects on leaf area (LA), specific leaf area (SLA), leaf dry matter content (LDMC), leaf relative water content (LRWC), net photosynthetic rate ( P n ), intercellular CO 2 concentration ( C i ), water use efficiency (WUE), and photosynthetic nitrogen use efficiency (PNUE). M. pauhoi seedlings under the treatment of NH 4 + -N:NO 3 - -N=1:9 had the highest LA, SLA, P n , WUE and PNUE. However, the seedlings under the treatment of NH 4 + -N:NO 3 - -N=9:1 had the lowest LDMC, leaf tissue density (LTD), LRWC and C i . Different NH 4 + -N/NO 3 - -N combined application did not affect leaf nitrogen content (LN) and leaf phosphorus content (LP), which were highest under the treatment of NH 4 + -N:NO 3 - -N=5:5. Across different NH 4 + -N/NO 3 - -N combined treatments, GD, TH, and RGR were significantly negatively correlated with SLA, while both GD and RGR were significantly negatively correlated with PNUE. Our results could provide theoretical basis for precise nutrient management and high-efficiency cultivation techniques during the seedling stage of the M. pauhoi .