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<jats:p>We report the magnetoresistance (MR), de Haas-van Alphen (dHvA) oscillations and the electronic structures of single-crystal PtGa. The large unsaturated MR is observed with the magnetic field <jats:italic>B</jats:italic> ∥ [111]. Evident dHvA oscillations with the <jats:italic>B</jats:italic> ∥ [001] configuration are observed, from which twelve fundamental frequencies are extracted and the spin-orbit coupling (SOC) induced band splitting is revealed. The light cyclotron effective masses are extracted from the fitting by the thermal damping term of the Lifshitz–Kosevich formula. Combining with the calculated frequencies from the first-principles calculations, the dHvA frequencies <jats:italic>F</jats:italic> <jats:sub>1</jats:sub>/<jats:italic>F</jats:italic> <jats:sub>3</jats:sub> and <jats:italic>F</jats:italic> <jats:sub>11</jats:sub>/<jats:italic>F</jats:italic> <jats:sub>12</jats:sub> are confirmed to originate from the electron pockets at <jats:italic>Γ</jats:italic> and <jats:italic>R</jats:italic>, respectively. The first-principles calculations also reveal the existence of spin-3/2 Rarita–Schwinger–Weyl fermions and time-reversal doubling of the spin-1 excitation at <jats:italic>Γ</jats:italic> and <jats:italic>R</jats:italic> with large Chern numbers of ± 4 when SOC is included.</jats:p>

<jats:p>We theoretically investigate physical properties of two-dimensional (2D) Fe<jats:sub>2</jats:sub>Ga<jats:sub>2</jats:sub>S<jats:sub>5</jats:sub> by employing first-principles calculations. It is found that it is an antiferromagnet with zigzag magnetic configuration orienting in the in-plane direction, with Néel temperatures around 160 K. The band structure of the ground state shows that it is a semiconductor with the indirect band gap of about 0.9 eV, which could be effectively tuned by the lattice strain. We predict that the carrier transport is highly anisotropic, with the electron mobility up to the order of ∼10<jats:sup>3</jats:sup> cm<jats:sup>2</jats:sup>/(V⋅s) much higher than the hole. These fantastic electronic properties make 2D Fe<jats:sub>2</jats:sub>Ga<jats:sub>2</jats:sub>S<jats:sub>5</jats:sub> a promising candidate for the future spintronics.</jats:p>

<jats:p>Two-dimensional (2D) ferromagnets with high Curie temperature have long been the pursuit for electronic and spintronic applications. CrI<jats:sub>3</jats:sub> is a rising star of intrinsic 2D ferromagnets, however, it suffers from weak exchange coupling. Here we propose a general strategy of self-intercalation to achieve enhanced ferromagnetism in bilayer CrI<jats:sub>3</jats:sub>. We show that filling either Cr or I atoms into the van der Waals gap of stacked and twisted CrI<jats:sub>3</jats:sub> bilayers can induce the double exchange effect and significantly strengthen the interlayer ferromagnetic coupling. According to our first-principles calculations, the intercalated native atoms act as covalent bridge between two CrI<jats:sub>3</jats:sub> layers and lead to discrepant oxidation states for the Cr atoms. These theoretical results offer a facile route to achieve high-Curie-temperature 2D magnets for device implementation.</jats:p>

<jats:p>We report an efficient and economical way for mass production of large-scale graphene films with high quality and uniformity. By using the designed scrolled copper-graphite structure, a continuous graphene film with typical area of 200 × 39 cm<jats:sup>2</jats:sup> could be obtained in 15 min, and the production rate of the graphene film and space utilization rate of the CVD reactor can reach 520 cm<jats:sup>2</jats:sup>⋅min<jats:sup>−1</jats:sup> and 0.38 cm<jats:sup>−1</jats:sup>⋅min<jats:sup>−1</jats:sup>, respectively. Our method provides a guidance for the industrial production of graphene films, and may also accelerate its large-scale applications.</jats:p>

<jats:p>We fabricated Sb<jats:sub>2</jats:sub>Se<jats:sub>3</jats:sub> thin film solar cells using tris(8-hydroxy-quinolinato) aluminum (Alq<jats:sub>3</jats:sub>) as an electron transport layer by vacuum thermal evaporation. Another small organic molecule of N,N’-bis(naphthalen-1-yl)-N,N’-bis(phenyl)benzidine (NPB) was used as a hole transport layer. We took ITO/NPB/Sb<jats:sub>2</jats:sub>Se<jats:sub>3</jats:sub>/Alq<jats:sub>3</jats:sub>/Al as the device architecture. An open circuit voltage (<jats:italic>V</jats:italic> <jats:sub>oc</jats:sub>) of 0.37 V, a short circuit current density (<jats:italic>J</jats:italic> <jats:sub>sc</jats:sub>) of 21.2 mA/cm<jats:sup>2</jats:sup>, and a power conversion efficiency (PCE) of 3.79% were obtained on an optimized device. A maximum external quantum efficiency of 73% was achieved at 600 nm. The <jats:italic>J</jats:italic> <jats:sub>sc</jats:sub>, <jats:italic>V</jats:italic> <jats:sub>oc</jats:sub>, and PCE were dramatically enhanced after introducing an electron transport layer of Alq<jats:sub>3</jats:sub>. The results suggest that the interface state density at Sb<jats:sub>2</jats:sub>Se<jats:sub>3</jats:sub>/Al interface is decreased by inserting an Alq<jats:sub>3</jats:sub> layer, and the charge recombination loss in the device is suppressed. This work provides a new electron transport material for Sb<jats:sub>2</jats:sub>Se<jats:sub>3</jats:sub> thin film solar cells.</jats:p>

<jats:p>Nuclear reaction rate <jats:italic>λ</jats:italic> is a significant factor in processes of nucleosyntheses. A multi-layer directed-weighted nuclear reaction network, in which the reaction rate is taken as the weight, and neutron, proton, <jats:sup>4</jats:sup>He and the remainder nuclei as the criteria for different reaction layers, is for the first time built based on all thermonuclear reactions in the JINA REACLIB database. Our results show that with the increase in the stellar temperature <jats:italic>T</jats:italic> <jats:sub>9</jats:sub>, the distribution of nuclear reaction rates on the R-layer network demonstrates a transition from unimodal to bimodal distributions. Nuclei on the R-layer in the region of <jats:italic>λ</jats:italic> = [1,2.5 × 10<jats:sup>1</jats:sup>] have a more complicated out-going degree distribution than that in the region of <jats:italic>λ</jats:italic> = [10<jats:sup>11</jats:sup>,10<jats:sup>13</jats:sup>], and the number of involved nuclei at <jats:italic>T</jats:italic> <jats:sub>9</jats:sub> = 1 is very different from the one at <jats:italic>T</jats:italic> <jats:sub>9</jats:sub> = 3. The redundant nuclei in the region of <jats:italic>λ</jats:italic> = [1, 2.5 × 10<jats:sup>1</jats:sup>] at <jats:italic>T</jats:italic> <jats:sub>9</jats:sub> = 3 prefer (<jats:italic>γ</jats:italic>, p) and (<jats:italic>γ</jats:italic>,<jats:italic>α</jats:italic>) reactions to the ones at <jats:italic>T</jats:italic> <jats:sub>9</jats:sub> = 1, which produce nuclei around the <jats:italic>β</jats:italic> stable line. This work offers a novel way to the big-data analysis on the nuclear reaction network at stellar temperatures.</jats:p>

<jats:p>We propose a fully symmetrical QKD system that enables quantum states to be prepared and measured simultaneously without compromising system performance. Over a 25.6 km fiber channel, we demonstrate point-to-point QKD operations with asymmetric Mach–Zehnder interferometer modules. Two interference visibilities of above 99% indicate that the proposed system has excellent stability. Consequently, the scheme not only improves the feasibility of distributing secret keys, but also enables QKD closer to more practical applications.</jats:p>

<jats:p>Concurrence is viewed as the most commonly approach for quantifying entanglement of two-qubit states, while intrinsic concurrence contains concurrence of four pure states consisting of a special pure state ensemble concerning an arbitrary two-qubit state. Thus, a natural question arises: Whether there is a specified relation between them. We firstly examine the relation between concurrence and intrinsic concurrence for the maximally nonlocal mixed state under a special unitary operation, which is not yet rigorously proved. In order to obtain a general result, we investigate the relation between concurrence and intrinsic concurrence using randomly generated two-qubit states, and derive an inequality relation between them. Finally, we take into account the relation between concurrence and intrinsic concurrence in open systems, and reveal the ratio of the two quantum resources, which is only correlated with the experiencing channels.</jats:p>

<jats:p>The deformations and the corresponding configurations of the odd-odd As isotopes are investigated using the adiabatic and configuration-fixed constrained triaxial relativistic mean field (RMF) theory. Energy minima with triaxial deformations and high-<jats:italic>j</jats:italic> particle-hole configurations are obtained in <jats:sup>72,74,76,78,80</jats:sup>As, where the chiral doublet bands are possible to appear. The existence of multiple chiral doublet (M<jats:italic>χ</jats:italic>D) is demonstrated in <jats:sup>74,76,78</jats:sup>As. Based on the calculated single-particle levels, we also find possible coexistence of chiral and pseudospin symmetries in the odd-odd As isotopes.</jats:p>

<jats:p>The geometry of fireballs in relativistic heavy ion collisions is approximated by a static box, which is infinite in two directions while finite in the other direction. The critical temperature of deconfinement phase transition is calculated explicitly in the MIT bag model at vanishing baryon density. It is found that the critical temperature shifts to a value higher than that in an unconstrained space.</jats:p>