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<jats:p>Using high-resolution angle-resolved and time-resolved photoemission spectroscopy, we have studied the low-energy band structures in occupied and unoccupied states of three ternary compounds GeBi<jats:sub>2</jats:sub>Te<jats:sub>4</jats:sub>, SnBi<jats:sub>2</jats:sub>Te<jats:sub>4</jats:sub> and Sn<jats:sub>0.571</jats:sub>Bi<jats:sub>2.286</jats:sub>Se<jats:sub>4</jats:sub> near the Fermi level. In previously confirmed topological insulator GeBi<jats:sub>2</jats:sub>Te<jats:sub>4</jats:sub> compounds, we confirmed the existence of the Dirac surface state and found that the bulk energy gap is much larger than that in the first-principles calculations. In SnBi<jats:sub>2</jats:sub>Te<jats:sub>4</jats:sub> compounds, the Dirac surface state was observed, consistent with the first-principles calculations, indicating that it is a topological insulator. The experimental detected bulk gap is a little bit larger than that in calculations. In Sn<jats:sub>0.571</jats:sub>Bi<jats:sub>2.286</jats:sub>Se<jats:sub>4</jats:sub> compounds, our measurements suggest that this nonstoichiometric compound is a topological insulator although the stoichiometric SnBi<jats:sub>2</jats:sub>Se<jats:sub>4</jats:sub> compound was proposed to be topological trivial.</jats:p>

<jats:p>In addition to electrical insulation properties, the thermal properties of nanodielectrics, such as glass transition temperature, thermal expansion coefficients, thermal conductivity, and mechanical properties, including Young’s modulus, bulk modulus, and shear modulus, are also very important. This paper describes the molecular dynamics simulations of epoxy resin doped with SiO<jats:sub>2</jats:sub> nanoparticles and with SiO<jats:sub>2</jats:sub> nanoparticles that have been surface grafted with hexamethyldisilazane (HMDS) at 10% and 20% grafting rates. The results show that surface grafting can improve certain thermal and mechanical properties of the system. Our analysis indicates that the improved thermal performance occurs because the formation of thermal chains becomes easier after the surface grafting treatment. The improved mechanical properties originate from two causes. First, doping with SiO<jats:sub>2</jats:sub> nanoparticles inhibits the degree of movement of molecular chains in the system. Second, the surface grafting treatment weakens the molecular repulsion between SiO<jats:sub>2</jats:sub> and epoxy resin, and the van der Waals excluded region becomes thinner. Thus, the compatibility between SiO<jats:sub>2</jats:sub> nanoparticles and polymers is improved by the grafting treatment. The analysis method and conclusions in this paper provide guidance and reference for the future studies of the thermal and mechanical properties of nanodielectrics.</jats:p>

<jats:p>The uniform distribution model of the surface donor states in AlGaN/GaN heterostructures has been widely used in the theoretical calculation. A common and a triple-channel AlGaN/GaN heterostructure Schottky barrier diodes have been fabricated to verify the models, but the calculation results show the uniform distribution model can not provide enough electrons to form three separate 2DEGs in the triple-channel AlGaN/GaN heterostructure. Our experiments indicate the uniform distribution model is not quite right, especially for the multiple-channel AlGaN/GaN heterostructures. Besides, it is found the exponential distribution model possibly matches the actual distribution of the surface donor states better, which allows the 2DEG to form in each channel structure during the calculation. The exponential distribution model would be helpful in the research field.</jats:p>

<jats:p>Size and morphology are critical factors in determining the electrochemical performance of the supercapacitor materials, due to the manifestation of the nanosize effect. Herein, different nanostructures of the CrN material are prepared by the combination of a thermal-nitridation process and a template technique. High-temperature nitridation could not only transform the hexagonal Cr<jats:sub>2</jats:sub>O<jats:sub>3</jats:sub> into cubic CrN, but also keep the template morphology barely unchanged. The obtained CrN nanostructures, including (i) hierarchical microspheres assembled by nanoparticles, (ii) microlayers, and (iii) nanoparticles, are studied for the electrochemical supercapacitor. The CrN microspheres show the best specific capacitance (213.2 F/g), cyclic stability (capacitance retention rate of 96% after 5000 cycles in 1-mol/L KOH solution), high energy density (28.9 Wh/kg), and power density (443.4 W/kg), comparing with the other two nanostructures. Based on the impedance spectroscopy and nitrogen adsorption analysis, it is revealed that the enhancement arised mainly from a high-conductance and specific surface area of CrN microspheres. This work presents a general strategy of fabricating controllable CrN nanostructures to achieve the enhanced supercapacitor performance.</jats:p>

<jats:p>Using first-principles calculations combined with the Boltzmann transport theory, we explore the thermoelectric properties of natural superlattice (SL) structure Sb<jats:sub>2</jats:sub>Te. The results show that n-type Sb<jats:sub>2</jats:sub>Te possesses larger Seebeck coefficient of 249.59 (318.87) μV/K than p-type Sb<jats:sub>2</jats:sub>Te of 219.85 (210.38) μV/K and low lattice thermal conductivity of 1.25 (0.21) W/mK along the in-plane (out-of-plane) direction at 300 K. The excellent electron transport performance is mainly attributed to steeper density of state around the bottom of conduction band. The ultralow lattice thermal conductivity of Sb<jats:sub>2</jats:sub>Te is mainly caused by low phonon group velocity and strong anharmonicity. Further analysis shows that the decrease of group velocity comes from flatter dispersion curves which are contributed by the Brillouin-zone folding. The strong anharmonicity is mainly due to the presence of lone-pair electrons in Sb<jats:sub>2</jats:sub>Te. Combining such a high Seebeck coefficient with the low lattice thermal conductivity, maximum n-type thermoelectric figure of merit (<jats:italic>ZT</jats:italic>) of 1.46 and 1.38 could be achieved along the in-plane and out-of-plane directions at room temperature, which is higher than the reported values of Sb<jats:sub>2</jats:sub>Te<jats:sub>3</jats:sub>. The findings presented here provide insight into the transport property of Sb<jats:sub>2</jats:sub>Te and highlight potential applications of thermoelectric materials at room temperature.</jats:p>

<jats:p>A multi-valued logic system is a promising alternative to traditional binary logic because it can reduce the complexity, power consumption, and area of circuit implementation. This article briefly summarizes the development of ternary logic and its advantages in digital logic circuits. The schemes, characteristics, and application of ternary logic circuits based on CMOS, CNTFET, memristor, and other devices and processes are reviewed in this paper, providing some reference for the further research and development of ternary logic circuits.</jats:p>

<jats:p>We report on the transport study of a double quantum dot (DQD) device made from a freestanding, single crystalline InSb nanosheet. The freestanding nanosheet is grown by molecular beam epitaxy and the DQD is defined by the top gate technique. Through the transport measurements, we demonstrate how a single quantum dot (QD) and a DQD can be defined in an InSb nanosheet by tuning voltages applied to the top gates. We also measure the charge stability diagrams of the DQD and show that the charge states and the inter-dot coupling between the two individual QDs in the DQD can be efficiently regulated by the top gates. Numerical simulations for the potential profile and charge density distribution in the DQD have been performed and the results support the experimental findings and provide a better understanding of fabrication and transport characteristics of the DQD in the InSb nanosheet. The achieved DQD in the two-dimensional InSb nanosheet possesses pronounced benefits in lateral scaling and can thus serve as a new building block for the developments of quantum computation and quantum simulation technologies.</jats:p>

<jats:p>Josephson parameter amplifier (JPA) is a microwave signal amplifier device with near-quantum-limit-noise performance. It has important applications in scientific research fields such as quantum computing and dark matter detection. This work reports the fabrication and characterization of broadband JPA devices and their applications in multi-qubit readout and squeezing of vacuum state. We use a process in which transmission lines and electrodes are made of niobium thin film and aluminum Josephson junctions are made by Dolan bridge technique. We believe this process is more convenient than the process we used previously. The whole production process adopts electron beam lithography technology to ensure high structural resolution. The test result shows that the gain value of the manufactured JPA can exceed 15 dB, and the amplification bandwidth is about 400 MHz. The noise temperature is about 400 mK at the working frequency of 6.2 GHz. The devices have been successfully used in experiments involving superconducting multi-qubit quantum processors. Furthermore, the device is applied to squeeze vacuum fluctuations and a squeezing level of 1.635 dB is achieved.</jats:p>

<jats:p>Payoff-driven strategy updating rule has always been adopted as a classic mechanism, but up to now, there have been a great many of researches on considering other forms of strategy updating rules, among which pursuing high fitness is one of the most direct and conventional motivations in the decision-making using game theory. But there are few or no researches on fitness from the perspective of others’ evaluation. In view of this, we propose a new model in which the evaluation effect with fitness-driven strategy updating rule is taken into consideration, and introduce an evaluation coefficient to present the degree of others’ evaluation on individual’s behavior. The cooperative individuals can get positive evaluation, otherwise defective individuals get negative evaluation, and the degree of evaluation is related to the number of neighbors who have the same strategy of individual. Through numerical simulation, we find that the evaluation effect of others can enhance the network reciprocity, thus promoting the cooperation. For a strong dilemma, the higher evaluation coefficient can greatly weaken the cooperation dilemma; for a weak one, the higher evaluation coefficient can make cooperator clusters spread faster, however, there is no significant difference in the level of cooperation in the final stable state among different evaluation coefficients. The cooperation becomes more flourish as the number of fitness-driven individuals increases, when all individuals adopt fitness-driven strategy updating rule, the cooperators can quickly occupy the whole population. Besides, we demonstrate the robustness of the results on the WS small-world network, ER random network, and BA scalefree network.</jats:p>

<jats:p>Based on the two-dimensional (2D) discrete Rulkov model that is used to describe neuron dynamics, this paper presents a continuous non-autonomous memristive Rulkov model. The effects of electromagnetic induction and external stimulus are simultaneously considered herein. The electromagnetic induction flow is imitated by the generated current from a flux-controlled memristor and the external stimulus is injected using a sinusoidal current. Thus, the presented model possesses a line equilibrium set evolving over the time. The equilibrium set and their stability distributions are numerically simulated and qualitatively analyzed. Afterwards, numerical simulations are executed to explore the dynamical behaviors associated to the electromagnetic induction, external stimulus, and initial conditions. Interestingly, the initial conditions dependent extreme multistability is elaborately disclosed in the continuous non-autonomous memristive Rulkov model. Furthermore, an analog circuit of the proposed model is implemented, upon which the hardware experiment is executed to verify the numerically simulated extreme multistability. The extreme multistability is numerically revealed and experimentally confirmed in this paper, which can widen the future engineering employment of the Rulkov model.</jats:p>