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• Understanding how strategic interactions influence trait evolution remains a challenge in evolutionary games. • The evolutionary RPS game investigates the evolution of three strategies under a fixed payoff matrix. • Exploring the impact of a dynamic instead of a fixed payoff matrix could change the dynamics of the game. • The adaptive RPS game, incorporating a dynamic payoff matrix, investigates how strategies change adaptively through trait evolution. The rock-paper-scissors (RPS) game is a classic model for exploring the performance of how multiple strategies interact and evolve over time. The classic RPS game assumes a fixed benefit and cost for each strategy against another one when two players meet, while its evolutionary game considers the frequency dynamics of the three strategies with each's fitness influenced by its net payoff. This may not reflect the complexity of real-world scenarios as strategies can co-adapt with each other. We introduce an adaptive RPS game that captures the dynamics of strategy densities with trait-mediated payoffs, and the adaptive dynamics of coevolving traits via incremental mutations leading to adaptively evolving payoffs. Results show that the adaptive RPS game approaches a steady state of strategy density, if any, faster than the evolutionary RPS game. The stable coexistence of all strategies in the evolutionary game can be easily destabilized in the adaptive game. Strategies that are allowed to adaptively change their traits also performed better and achieved greater strategy densities than those fixed strategies in the adaptive game. The coevolving strategies in the adaptive RPS game exhibit complex and diverse attractors in the trait space, sensitive to both initial conditions and model parameters, but exhibiting positive payoffs with greater benefits than costs. These findings highlight how adaptive games enhance strategy performance by sacrificing eco-evolutionary dynamic stability. [ABSTRACT FROM AUTHOR]

In this paper, we have proposed a direct current model and noise model, which are physically based on the metal oxide thin‐film transistors (TFTs) operation mechanisms. Based on the calculated surface potential and the Pao‐Sah double integral formula, the direct current characteristics of metal oxide TFTs are predicted. According to low‐frequency noise (LFN) models, the mechanism affecting the noise properties of metal oxide TFTs is analyzed, and the density of trap states near the device interface is extracted by the LFN method. Through comparisons between model results and numerical iteration or experimental data, the validity of the proposed models is strongly supported. Due to the simplicity of algorithm and clear physical conception, it is easy to implement these models into circuit simulators. [ABSTRACT FROM AUTHOR]

Bismuth ferrite belongs to magnetoelectric compounds which join, in the same crystal phase, two mutually excluding order parameters like magnetic and ferroelectric. In case of BiFeO3 both of these transition temperatures are considerably above room temperature what is important form the point of view of applications. In this paper electronic band structure calculations are presented. In the calculations, hybrid exchange interaction potential is applied, which gives the possibility to obtain correct insulating character of the compound without application of arbitrary Hubbard U parameter. The calculated densities of electronic states and magnetic properties are described. [ABSTRACT FROM AUTHOR]

In the present paper, we have conducted both theoretical and experimental investigations on thin films of lead sulfide (PbS). The structural and morphological properties of these films, which were prepared using the spray pyrolysis method, were analyzed utilizing X-ray diffraction (XRD) and scanning electron microscopy (SEM). Theoretical calculations were performed employing the first principles full potential linearized augmented plane wave (FP-LAPW) approach. The findings of this study reveal that the PbS film that was deposited is polycrystalline and possesses a rock-salt structure. The SEM image depicts a planar structure with dimensions ranging from 480 to 930 nm. The results obtained through energy dispersive spectroscopy (EDS) indicate high crystalline quality, and the film surface exhibits a rough texture and a dense morphology. In terms of its behavior, PbS acts as a semiconductor with a direct optical band gap situated at the L point of the Brillouin zone (BZ). The density of states on both sides of the band gap is primarily of s-p character. The ionic nature of PbS can be attributed to charge transfer. A substantial level of agreement has been observed between the experimental and theoretical results. Our ongoing research endeavors aim to explore biosensors and their various applications. The novelty of this work lies in the combined study of the structural and morphological properties of PbS films grown using the spray pyrolysis technique, employing both experimental and theoretical approaches. This paper describes a comprehensive approach to understanding bulk and thin-film PbS materials through theory and experimentation. [ABSTRACT FROM AUTHOR]

We present here a combined theoretical and experimental investigation on hysteresis improvement of LTPS TFTs via optimizing hydrogen content in poly‐silicon and adjusting density of states at poly‐Si/oxide interface. It can be demonstrated that hysteresis seems to be more dependent on the difference in trap density between the bandedge and midgap energy levels. A new method named just noticeable current difference (JND_Current) is employed to evaluate TFT reliability and short‐term image sticking. Incorporating the optimized processes of a‐Si deposition, cleaning conditions before gate‐insulator (GI) deposition and contact hole annealing is helpful to improve instability of LTPS TFTs. The hysteresis level (ΔVth) can be reduced to 0.11V, and also an improvement in quantized level of short‐term image sticking by 35%. [ABSTRACT FROM AUTHOR]

In the quest to enhance the mechanical properties of CuP alloys, particularly focusing on the Cu3P phase, this study introduces a comprehensive investigation into the effects of various alloying elements on the alloy's performance. In this paper, the first principle of density universal function theory and the projection-enhanced wave method under VASP 5.4.4 software are used to recalculate the lattice constants, evaluate the lattice stability, and explore the mechanical properties of selected doped elements such as In, Si, V, Al, Bi, Nb, Sc, Ta, Ti, Y and Zr, including shear, stiffness, compression, and plasticity. The investigation reveals that strategic doping with In and Si significantly enhances shear resistance and stiffness, while V addition notably augments compressive resistance. Furthermore, incorporating Al, Bi, Nb, Sc, Ta, Ti, V, Y, and Zr has substantially improved plasticity, indicating a broad spectrum of mechanical enhancement through precise alloying. Crucially, the validation of our computational models is demonstrated through hardness experiments on Si and Sn-doped specimens, corroborating the theoretical predictions. Additionally, a meticulous analysis of the states' density further confirms our computational approach's accuracy and reliability. This study highlights the potential of targeted alloying to tailor the mechanical properties of Cu3P alloys and establishes a robust theoretical framework for predicting the effects of doping in metallic alloys. The findings presented herein offer valuable insights and a novel perspective on material design and optimization, marking a significant stride toward developing advanced materials with customized mechanical properties. [ABSTRACT FROM AUTHOR]

Context: The key factor in designing heat-resistant energetic materials is their thermal sensitivity. Further research and prediction of thermal sensitivity remains a great challenge for us. This study is based on first-principles calculations and establishes a theoretical model, which comprehensively considers band gap, density of states, and Young's modulus to obtain a empirical parameter Ψ. A quantitative relationship was established between the new parameter and the thermal decomposition temperature. The value of Ψ is calculated for 10 energetic materials and is found to have a strong correlation with the experimental thermal decomposition temperature. This further proves the reliability of our model. Specifically, the larger the value of Ψ, the higher the thermal decomposition temperature, and the more stable the energetic material will be. Therefore, to some extent, we can use the new parameter Ψ calculated by the model to predict thermal sensitivity. Methods: Based on first-principles, this paper used the Cambridge Serial Total Energy Package (CASTEP) module of Materials Studio (MS) for calculations. The Perdew-Burke-Ernzerhof (PBE) functionals in Generalized Gradient Approximation (GGA) method as well as the Grimme dispersion correction was used in this paper. [ABSTRACT FROM AUTHOR]

By systematically varying the boron concentration near the oxide/4H–SiC interface within a specifically designed boron-diffusion layer oxide structure, this paper explores the influence of boron concentration on interface state density and near-interface trap density in 4H–SiC MOS capacitors. Additionally, the effect of boron near the oxide/4H–SiC interface on device stability under elevated temperature conditions was examined. The boron species were introduced into the SiO2/4H–SiC interface by spin coating followed by annealing, whose temperature controls the amount of boron present in the near interface region. It is suggested that a higher concentration of boron leads to a better trap passivation effect while preserving the stability of flat band voltage. [ABSTRACT FROM AUTHOR]

We examine the impact of temperature (T) on the Seebeck coefficient S, i.e., the T dependence of S for a single-component molecular conductor [Pd(dddt)2] (dddt = 5,6-dihydro-1,4-dithiin-2,3-dithiolate) with a half-filled band, where the coefficient is obtained from a ratio of the thermal conductivity to the electrical conductivity. The present paper demonstrates theoretically the novel result of large anisotropy in the Seebeck coefficient components of three-dimensional Dirac electrons in a molecular conductor. The conductor exhibits a nodal line with the energy variation around the chemical potential and provides the density of states (DOS) with a minimum. Using a threedimensional tight-binding (TB) model in the presence of both impurity and electron–phonon (e–p) scatterings, we study the Seebeck coefficient Sy for the molecular stacking and the most conducting direction. The impact of T on Sy exhibits a sign change, where Sy > 0 with a maximum at high temperatures and Sy < 0 with a minimum at low temperatures. The T dependence of Sy suggests that the contribution from the conduction (valence) band is dominant at low (high) temperatures. Further, it is shown that the the Seebeck coefficient components for perpendicular directions Sx and Sz are much smaller than Sy and present no sign change, in contrast to Sy. These results are analyzed in terms of the spectral conductivity as a function of the energy ϵ close to the chemical potential μ. [ABSTRACT FROM AUTHOR]

Recent studies show that zinc oxide (ZnO) nanostructures have promising potential as an absorbing material. In order to improve the optoelectronic properties of the initial system, this paper considers the process of adsorbing multilayer graphene-like ZnO onto a Si (111) surface. The density of electron states for two- and three-layer graphene-like zinc oxide on the Si (111) surface was obtained using the Vienna ab-initio simulation package by the DFT method. A computer model of graphene-like Zinc oxide on a Si (111)-surface was created using the DFT+U approach. One-, two- and three-plane-thick graphene-zinc oxide were deposited on the substrate. An isolated cluster of Zn3O3 was also considered. The compatibility of g-ZnO with the S (100) substrate was tested, and the energetics of deposition were calculated. This study demonstrates that, regardless of the possible configuration of the adsorbing layers, the Si/ZnO structure remains stable at the interface. Calculations indicate that, in combination with lower formation energies, wurtzite-type structures turn out to be more stable and, compared to sphalerite-type structures, wurtzite-type structures form longer interlayers and shorter interplanar distances. It has been shown that during the deposition of the third layer, the growth of a wurtzite-type structure becomes exothermic. Thus, these findings suggest a predictable relationship between the application method and the number of layers, implying that the synthesis process can be modified. Consequently, we believe that such interfaces can be obtained through experimental synthesis. [ABSTRACT FROM AUTHOR]

The contents of alkali and alkaline earth metals are higher in Zhundong coal, and there are serious problems of slagging and fouling during the combustion process. Therefore, it is of great significance to reveal the mechanism of slagging and fouling in the boiler of Zhundong coal. In this paper, first-principle calculations based on density functional theory are used to study the competition mechanism of alkaline metal oxides during the combustion process in Zhundong coal by establishing the Na2O(110)/CaO(100)-SiO2(100) double-layer interface model. The results show that the bond lengths of the surface of Na2O(110) and CaO(100) with SiO2(100) after adsorption were generally lengthened and the value of bond population became smaller, which formed a stable binding energy during the reaction. The electron loss of Na is 0.05 e, the electron loss of Ca is 0.03 e, and the electron loss of Na2O is greater than that of CaO. The charge transfer on the surface of Na2O with SiO2 is obviously higher than that of CaO and the orbital hybridization on the surface of CaO with SiO2 is weaker than that on the surfaces of Na2O with SiO2. Na2O is easier to react with SiO2 than CaO. The adsorption energies on the surface of Na2O and CaO with SiO2 are −5.56 eV and −0.72 eV, respectively. The adsorption energy of Na2O is higher than that of CaO, indicating that Na2O is more prone to adsorption reactions and formation of Na-containing minerals and other minerals, resulting in more serious slagging. In addition, the XRD analyses at different temperatures showed that Na-containing compounds appeared before Ca-containing ones, and the reaction activity of Na2O is stronger than that of CaO in the reaction process. The experimental results have good agreement with the calculation results. This provides strong evidence to reveal the slagging and fouling of Zhundong coal. [ABSTRACT FROM AUTHOR]

Inbuilt high energy band gap and resistivity cause harm to the intrinsic molybdenum trioxide (MoO3) for utilizing it directly in gas sensing and optoelectronic devices. Doping with transition metal ions can be an optimistic solution to these problems. By doping four side of modification of a material is possible. At first, doping can curtail the width of the energy band of semiconductor materials, thereby largely boosting the photo-sensitivity of the material and intensifying the light consumption that is more suitable for anti-laser devices and light source substances. The second is that doping can widen the material's band gap, which can significantly reduce the purities of the substance, improve absorbance, and make it suitable for strong interference semiconductor films and aperture materials. Third, changing the material's charge carrier density and effective mass can significantly improve conductivity. This is mostly relevant for conductive devices and photosensitive materials. Finally, changing the material's valance electron location influences the magnetic moment created by the spin of elementary particles in the entire system, allowing the magnetic characteristics of the substance to be regulated, which is especially useful for diluted magnetic semiconductor (DMS) materials. The investigation report of the structural, electrical, and optical characteristics of Cobalt (Co)-doped orthorhombic-phase MoO3 utilizing plane-wave pseudo-potential technique based on first-principles computation is presented in this paper. The computation has been executed using density a functional theory (DFT)-based CASTEP computer program with the generalized gradient approximation (GGA) together with the Perdue-Burke-Ernzerhof (PBE) exchange–correlation function. Acquired structural parameters present good consistency with the former reported experimental data. The resultant electronic band structure reveals that pure MoO3 shows an indirect energy band gap of 1.873 eV/2.312 eV whereas Co doping causes band narrowing of about 0.94 eV/1.36 eV with PBE/HSE techniques. The total and partial density of states (PDOS) have been studied comparatively, for pure and Co-doped MoO3, respectively. The absorption coefficient, loss function, reflectivity, refractive index, extinction coefficient, dielectric function, along with optical conductivity have also been determined to analyze the optical properties of Co-doped MoO3. Co-doped MoO3 offers higher conductivity while decreasing resistivity, compared to the undoped case. The present study ensures that Co-doped α- MoO3 can be competently employed as a functional material in gas sensing and optoelectronic devices. [ABSTRACT FROM AUTHOR]

The modern textbook analysis of the thermal state of photons inside a three-dimensional reflective cavity is based on the three quantum numbers that characterize photon's energy eigenvalues coming out when the boundary conditions are imposed. The crucial passage from the quantum numbers to the continuous frequency is operated by introducing a three-dimensional continuous version of the three discrete quantum numbers, which leads to the energy spectral density and to the entropy spectral density. This standard analysis obscures the role of the multiplicity of energy eigenvalues associated to the same eigenfrequency. In this paper we review the past derivations of Bose's entropy spectral density and present a new analysis of energy spectral density and entropy spectral density based on the multiplicity of energy eigenvalues. Our analysis explicitly defines the eigenfrequency distribution of energy and entropy and uses it as a starting point for the passage from the discrete eigenfrequencies to the continuous frequency. [ABSTRACT FROM AUTHOR]

The transient photocurrent is one of the key parameters of the spatial radiation effect of photoelectric devices, and the energy level defect affects the transient photocurrent. In this paper, by studying the deep level transient spectrum of a self-designed Schottky diode, the defect properties of the interface region of the anode metal AlCu and Si caused by high-temperature annealing at 150 ℃, 200 ℃ and 300 ℃ for 1200 h have been quantitatively analyzed. The study shows that the defect is located at the position of + 0.41 eV on the valence band, the concentration is 2.8 × 1013/cm2, and the capture cross section is σ = 8.5 × 1017. The impurity energy level mainly comes from the diffusion of Al atom in anode metal. We found that the defect did not cause the electrical performance degradation and obvious morphology change of the device, but the transient photocurrent increased significantly. The reason is that the high temperature treatment results in a growth in the density of states at the interface between AlCu–Si. The more mismatched dislocations and recombination center increased the reverse current of the heterojunction. The above view is proved by the TCAD simulation test. [ABSTRACT FROM AUTHOR]

In object-tracking and state-estimation problems, ambiguous evidence such as imprecise measurements and the absence of detections can contain valuable information and thus be leveraged to further refine the probabilistic belief state. In particular, knowledge of a sensor's bounded field of view (FoV) can be exploited to incorporate evidence of where an object was not observed. This paper presents a systematic approach for incorporating knowledge of the FoV geometry, position, and object inclusion/exclusion evidence into object state densities and random finite set multiobject cardinality distributions. The resulting state estimation problem is nonlinear and solved using a new Gaussian mixture approximation based on recursive component splitting. Based on this approximation, a novel Gaussian mixture Bernoulli filter for imprecise measurements is derived and demonstrated in a tracking problem using only natural language statements as inputs. This paper also considers the relationship between bounded FoVs and cardinality distributions for a representative selection of multiobject distributions, which can be used for sensor planning, as is demonstrated through a problem involving a multi-Bernoulli process with up to 100 potential objects. [ABSTRACT FROM AUTHOR]

Due to the difficulty of forming a low Schottky barrier at the interface of a metal/SiC contact, preparing Ohmic contacts is still a key technical problem in developing SiC devices. In this paper, the effects of MoS2 intercalation on the interface properties of metal/SiC (Al, Ag, Ti, Au, and Mg) systems were investigated by first-principles calculation. The calculations show that all the metal/SiC contacts exhibit p-type Schottky contacts with strong Fermi level pinning (FLP) at the interfaces. After inserting a layer of MoS2, the Schottky barrier heights are significantly reduced. All the metal/MoS2/SiC systems are tuned to be n-type Ohmic contacts. By calculating and analyzing electron localization functions, projected band structure, partial density of states, and planar-averaged charge density difference, the Ohmic contact formation mechanism may be due to the saturation of dangling bonds of the SiC surface, the reduction in metal-induced gap states, the formation of interface dipole layer, and the shift of FLP position to the interface of metal/MoS2. [ABSTRACT FROM AUTHOR]

Boron carbide (B 4 C) has been well studied both theoretically and experimentally in its bulk form due to its exceptional hardness and use as a high-temperature thermoelectric. However, the properties of its two-dimensional nanosheets are not well established. In this paper, using van der Waals-corrected density-functional theory simulations, we show that bulk B 4 C can be cleaved along different directions to form B 4 C nanosheets with low formation energies. We find that there is minimal dependence of formation energies on cleavage planes and surface terminations, even though the bulk is not van der Waals layered. This anomalous stability of B 4 C nanosheets is found to be a result of surface reconstructions that are unique to B-rich systems. While the density of states of the bulk B 4 C indicate that it is a semiconductor, the B 4 C nanosheets are found to be predominantly metallic. We attribute this metallic behavior to a redistribution of charges on the surface bonds of the films. The Seebeck coefficients of the B 4 C films remain comparable to those of the bulk and are nearly constant as a function of temperature. Our results provide guidance for experimental synthesis efforts and future application of B 4 C nanosheets in nanoelectronic and thermoelectric applications. [ABSTRACT FROM AUTHOR]

This study demonstrates the effect of nitrogen doping on the surface state densities (Nss) of monolayer MoS2 and its effect on the responsivity and the response time of the photodetector. Our experimental results shows that by doping monolayer MoS2 by nitrogen, the surface state (Nss) increases thereby increasing responsivity. The mathematical model included in the paper supports the relation of photocurrent gain and its dependency on trap level which states that the increasing the trap density increases the photocurrent gain and the same is observed experimentally. The experimental results at room temperature revealed that nitrogen doped MoS2 have a high NSS of 1.63 X 1013 states/m2/eV compared to undoped MoS2 of 4.2 x 1012 states/m2/eV. The increase in Nss in turn is the cause for rise in trap states which eventually increases the value of photo responsivity from 65.12 A/W (undoped MoS2) to 606.3 A/W (nitrogen doped MoS2). The response time calculated for undoped MoS2 was 0.85 sec and for doped MoS2 was 0.35 sec. Finally, to verify the dependence of surface states on the responsivity, the surface states were varied by varying temperature and it was observed that upon increment in temperature, the surface states decreases which causes the responsivity values also to decrease. [ABSTRACT FROM AUTHOR]

This paper presents numerical simulation and compact modeling of 2,7-Dioctyl {1} benzothieno {3,2-b}{1} benzothiophene (C8-BTBTC8) organic semiconductor-based TFT. It shows the entire modeling process flow of this organic semiconductor (OSC) and tests the device realization using a ring oscillator. The paper comprises OSC characterisation, band-gap modeling, electrostatic modeling, and capacitance modeling. The TCAD model consists of the Hopping and Pool Frenkel premise and characterizes the Density of State (DOS) for traps in deep and tail states. The findings from this research provide valuable information for improving OTFT models, enhancing their predictive accuracy, and advancing the understanding of organic semiconductor device behavior. The electrostatics demonstrate device structure dependency. [ABSTRACT FROM AUTHOR]

The complex theoretical analysis of the density of states, band structures, and Fermi surfaces, based on predictions of the density functional theory methods, unveils the unique electronic properties of the LaZn1−xBi2 system. In this paper, the Zn vacancies (for x = 0.5 ) were modeled using a modified unit cell of lower symmetry than that for a fully stoichiometric one (for x = 0 ). The existence of several Dirac-like features in the electronic band structures was found. Some of them were found to be intimately associated with the nonsymmorphic symmetry of the system, and these were investigated in detail. The calculated Fermi surface shapes, as well as the Fermi velocity values (up to ∼1.2 × 10 6 m/s), are in good agreement with other analogous square-net Dirac semimetals. The combination of charge-carrier uncompensation, relatively small band splitting, and the tolerance factor for square-net semimetals t ≤ 0.95 for LaZn0.5Bi2, constitutes a very promising indicator of the topological features of this system, warranting further experimental studies. [ABSTRACT FROM AUTHOR]

CO and HCHO are the main pyrolysis gases in long-term running dry-type reactors, and thus the diagnosis of thermal insulation faults inside such devices can be realized by sensing these gases. In this paper, a single Au atom-decorated WS2 (Au-WS2) monolayer is proposed as an original sensing material for CO or HCHO detection to evaluate the operation status of dry-type reactors. It was found that the Au atom prefers to be adsorbed at the top of the S atom of the pristine WS2 monolayer, wherein the binding force is calculated as −3.12 eV. The Au-WS2 monolayer behaves by chemisorption upon the introduction of CO and HCHO molecules, with the adsorption energies of −0.82 and −1.01 eV, respectively. The charge density difference was used to analyze the charge-transfer and bonding behaviors in the gas adsorptions, and the analysis of density of state as well as band structure indicate gas-sensing mechanisms. As calculated, the sensing responses of the Au-WS2 monolayer upon CO and HCHO molecule introduction were 58.7% and −74.4%, with recovery times of 0.01 s and 11.86 s, respectively. These findings reveal the favorable potential of the Au-WS2 monolayer to be a reusable and room-temperature sensing candidate for CO and HCHO detections. Moreover, the work function of the Au-WS2 monolayer was decreased by 13.0% after the adsorption of CO molecules, while it increased by 1.2% after the adsorption of HCHO molecules, which implies its possibility to be a work-function-based gas sensor for CO detection. This theoretical report paves the way for further investigations into WS2-based gas sensors in some other fields, and it is our hope that our findings can stimulate more reports on novel gas-sensing materials for application in evaluating the operation conditions of dry-type reactors. [ABSTRACT FROM AUTHOR]

The capacitance–voltage (C – V) and conductance–voltage (G – V) characteristics of GaN metal–insulator–semiconductor (MIS) structures have a frequency dependence due to the capture and emission of electrons by the high density of the interface states. However, the details of how an interface state affects C – V and G – V characteristics is still not well understood. In this paper, we report a numerical modeling method that can simulate the frequency dependent C – V and G – V characteristics of GaN MIS structures. [ABSTRACT FROM AUTHOR]

Detecting the decomposition components of SF6 insulating gas is recognized as an effective means to monitor the operating status of the SF6 insulating switch. In this paper, the adsorption characteristics of a new two-dimensional material GeSe for five SF6 decomposition gases (SO2, SOF2, SO2F2, H2S and HF) are reported by first-principles simulation. Through the analysis of the change of energy band structure, density of states distribution, and gas desorption time, it is found that GeSe has the potential as a gas-sensitive material for the selective detection of SO2F2, and the computational work in this paper provides theoretical guidance for the development of new gas-sensitive sensors applied in monitoring SF6 insulated switches. [ABSTRACT FROM AUTHOR]

Using the first-principles calculation, two doping two-dimensional (2D) BN (boron nitride) polymorphs are constructed in this work. The two doping 2D BN polymorphs B5N6Al and B5N6C sheets are thermally stable under 500 K. All the B6N6, B5N6Al, and B5N6C sheets are semiconductor materials with indirect band gaps on the basis of a hybrid functional. The anisotropic calculation results indicate that Young's modulus (E) and Poisson's ratio (v) of the B6N6, B5N6Al, and B5N6C sheets are anisotropic in the xy plane. In addition, the magnetic properties of the B6N6, B5N6Al, and B5N6C sheets have also been investigated. According to the calculation of the magnetic properties, B6N6 sheet does not exhibit magnetism, while it shows weak magnetism after doping carbon atom to the BN sheet. This paper explores the influence mechanism of doping different atoms on the basic physical properties of two-dimensional BN sheets. It not only constructs a relationship between structure and performance but also provides theoretical support for the performance regulation of BN materials. [ABSTRACT FROM AUTHOR]

SF6/N2 mixture is an alternative gas of SF6, which is already used in electrical equipment. When a malfunction occurs, SF6/N2 will decompose and further react with trace water and oxygen to produce nitrogen-containing gases such as NO, NO2, N2O and NF3. It is necessary to monitor these gases to ensure the safe operation of the equipment. This paper is based on density functional theory (DFT), the nanomaterial Ti3C2T x doped with Au atom was selected as sensing material. The result shows that Au/Ti3C2T x has larger adsorption energy when NO and NO2 adsorbed on the surface, the stable structures were conformed more easily with NO and NO2 compared with N2O and NF3. The density of states analysis and the frontier molecule orbital analysis reveal more change of the system before and after NO and NO2 adsorption, suggesting the material showed good sensitivity performance to NO and NO2. Thus, Au/Ti3C2T x is considered to have the potential for sensing NO and NO2. [ABSTRACT FROM AUTHOR]

In this paper, we investigated an optimal investment problem of a defined contribution (DC) pension plan under a joint Value-at-Risk (VaR) and an expected shortfall (ES) constraint. By using a martingale method, we transformed a dynamic optimization problem to a static pointwise optimization problem and derived the closed-form representations of the optimal wealth and portfolio processes in terms of the state price density. Numerical results showed that in comparison to only an ES constraint or a VaR constraint, the joint VaR-ES constraint can not only improve risk management for the bad economic states but also lower the volatility of the optimal terminal wealth. [ABSTRACT FROM AUTHOR]

In this paper, a complete lattice study of thorium telluride (ThTe) in the effects of three-body interaction (TBI) in the framework of RIM and RSM models is reported. By use of the present model, I have theoretically reported elastic constants, pressure derivatives, dispersion relation curve, specific heat curve, combined density of states (CDS) and equation of state of the ThTe compound. The achieved results are good with experimentally reported results and have given very important information about this compound for further investigation. [ABSTRACT FROM AUTHOR]

Ultrahigh-energy density (UHED) states greater than 1 Gbar pressure are typically observed under extreme conditions, such as in the core of an inertial confinement fusion implosion. A novel alternative approach for generating volumetric UHED states is to use nanowire arrays irradiated with a femtosecond ultrahigh-intensity laser. In this paper, we present an experimental investigation on laser absorption and energy transport in nanowire arrays irradiated with a picosecond kilojoule petawatt laser. The laser–target interactions were studied by measuring the x-ray emission and escaping hot electrons from a bare Cu foil and a foil with a nanowire array grown on its surface. The measured Cu-Kα and He-α emissions from the nanowire array were higher than those from the flat foil. In addition, hot electrons observed from the front surface of the nanowire array were enhanced. On the other hand, despite the stronger Kα emission from the nanowire array and the enhancement of hot electrons escaping from the front surface of the nanowire array, the number of hot electrons observed from the rear side of the flat foil target was slightly lower than that of the flat foil. A comparison of the experimental results with the results of a two-dimensional particle-in-cell simulation code suggested that the magnetic fields generated around the periodic nanowire array trap hot electrons, improving the electron-to-target energy coupling and efficiently producing UHED states. [ABSTRACT FROM AUTHOR]

Forming a hetero-interface is a materials-design strategy that can access an astronomically large phase space. However, the immense phase space necessitates a high-throughput approach for an optimal interface design. Here we introduce a high-throughput computational framework, InterMatch, for efficiently predicting charge transfer, strain, and superlattice structure of an interface by leveraging the databases of individual bulk materials. Specifically, the algorithm reads in the lattice vectors, density of states, and the stiffness tensors for each material in their isolated form from the Materials Project. From these bulk properties, InterMatch estimates the interfacial properties. We benchmark InterMatch predictions for the charge transfer against experimental measurements and supercell density-functional theory calculations. We then use InterMatch to predict promising interface candidates for doping transition metal dichalcogenide MoSe2. Finally, we explain experimental observation of factor of 10 variation in the supercell periodicity within a few microns in graphene/α-RuCl3 by exploring low energy superlattice structures as a function of twist angle using InterMatch. We anticipate our open-source InterMatch algorithm accelerating and guiding ever-growing interfacial design efforts. Moreover, the interface database resulting from the InterMatch searches presented in this paper can be readily accessed online. Predicting properties at the interface of materials is crucial for advanced materials design. Here, the authors introduce a high-throughput computational framework, InterMatch, for predicting several properties of an interface by using the databases of individual bulk materials. [ABSTRACT FROM AUTHOR]

In the pursuit of developing high-performance low-dimensional spintronic devices, two-dimensional van der Waals heterostructures comprising non-magnetic nitride and ferromagnetic materials have emerged as a crucial area of investigation. This paper proposes a novel structure that employs hexagonal two-dimensional semiconductor GaN flanked by two half-metallic two-dimensional CrN layers. The stability of the proposed structure is verified via first-principles calculations, which indicate good thermodynamic and magnetic stability. The transport characteristics of electrons in the structure are analyzed through the Band structures and density of states. Specifically, the study examines the spin polarizability of parallel and anti-parallel magnetic configurations of the CrN/GaN/CrN vdW heterostructure, and the results demonstrate a significant spin valve effect. Overall, the study establishes the potential of the CrN/GaN/CrN vdW heterostructure as a candidate for the development of innovative spintronic devices. [ABSTRACT FROM AUTHOR]

The CdIn2S4 semiconductor is considered a potential host for the implementation of intermediate band solar cells due to its ideal bandgap value and excellent photoelectric property. In this paper, the electronic structures of group IV elements (Si, Ge, Sn, and Pb)-doped CdIn2S4 have been investigated by using hybrid density functional calculations. In the case of Ge, Sn, and Pb doping, an isolated and partially occupied intermediated band with delocalized characteristics could be created in the bandgap of the host. The results of the projected density of states reveal that the intermediated band is derived from the hybridization between the S-3p and dopant-ns states. Thanks to the assistance of the impurity band, the optical absorption ability of the intermediate band semiconductor is greatly enhanced. Based on the detailed balance theory, the theoretical efficiencies of intermediate band solar cells made by Ge- and Pb-doped CdIn2S4 are estimated to be 45.0% and 49.2%, respectively, which are superior to the Shockley and Queisser limit (40.7%) of a single junction photovoltaic device. Moreover, the experimental synthesis of these impurity semiconductors is relatively feasible because substitutional doping at the octahedral position is energetically favorable. These findings would be helpful to the development of a high-efficiency intermediate band solar cell. [ABSTRACT FROM AUTHOR]

Pseudo-magnetic field (PMF) in deformed graphene has been proposed as a promising and flexible method to quantum-confine electronic states and create gaps in the local density of states. Motivated by this perspective, we numerically analyze various different configurations leading to electronic localization and band flattening in periodically strained graphene. In particular, we highlight the existence of a fine structure in the pseudo-Landau levels confined in large-PMF regions, the emergence of states confined to PMF nodes as well as of snake-like orbits. In our paper, we further analyze the importance of the relative rotation and asymmetry of the strain lattice with respect to the atomic lattice and show how it can be used to modulate the PMF periodicity and to create localized orbits far from the strain points. Possible implementations and applications of the simulated structures are discussed. [ABSTRACT FROM AUTHOR]

The structural stability, electrical properties (energy band structure, density of states) and optical properties of AlAs/InP/CdS multilayer heterojunctions have been systematically investigated using first-principles calculations based on density functional theory. The A-type structure in this paper is the most stable, with a direct band gap of 0.477 eV. The heterojunction is strongly bonded due to the aggregation of electrons among all three layers of atoms, the formation of van der Waals forces between the atoms and the formation of orbital hybridization among some of the atoms. The optoelectronic properties of multilayer heterojunctions are superior to those of single layers. AlAs/InP/CdS multilayer heterojunctions have high absorption peaks in the UV and visible regions and also have good absorption capability in the infrared. The AlAs/InP/CdS multilayer heterojunction has a stable structure and excellent optoelectronic properties, and has great potential and broad application prospects in the fields of visible light absorption, photocatalysis, infrared light and ultraviolet light detection. [ABSTRACT FROM AUTHOR]

In this paper, the effects of carbon nanotube defects and a copper surface oxide layer on a carbon nanotube–copper interface were studied via first-principles. A defect-free CNT-Cu interface, Stone–Wales defect CNT-Cu interface, single-hole and double-hole defect CNT-Cu interface, and Cu2O-Cu interface were simulated and calculated. By simulating the differential charge density, atomic population, bond population and density of states of the interface model, the effects of various defects on the interface bonding and electrical conductivity of the composites during the preparation of the CNT-reinforced copper matrix composites were analyzed, which provided theoretical guidance for the preparation of CNT/Cu composites. After that, copper matrix composites with different CNT defect contents were prepared via different rolling deformation processes. Their hardness and electrical conductivity were tested, and the results were consistent with the results obtained via the first-principles calculations. [ABSTRACT FROM AUTHOR]

In this paper, we establish the Anderson localization, strong dynamical localization and the (1 2 -) -Hölder continuity of the integrated density of states (IDS) for some multi-dimensional discrete quasi-periodic (QP) Schrödinger operators with asymmetric C 2 -cosine type potentials. We extend both the iteration scheme of Cao-Shi-Zhang (Commun Math Phys 404(1):495–561, 2023) and the interlacing method of Forman and VandenBoom (Localization and Cantor spectrum for quasiperiodic discrete Schrödinger operators with asymmetric, smooth, cosine-like sampling functions. arXiv:2107.05461, 2021) to handle asymmetric Rellich functions with collapsed gaps. [ABSTRACT FROM AUTHOR]

The DFT method was used to predict the formation energies and quadrupole coupling constants CQ in a series of borophosphates: Li3BP2O8, Li2NaBP2O8, Na3BP2O8, Li2B3PO8, Na5B2P3O13, LiNa2B5P2O14 and Na3B6PO13 composed of different networks and different amounts of borate and phosphate units. The change in formation energies with increasing number of B atoms in this series is attributed to the multiplicity of boron sites and is explained by density of states calculations. The calculated CQ values of 7Li, 23Na and 11B are correlated with the coordination and distortion of polyhedra to elucidate the influence of local and more distant environments. As for the CQ of 11B, it should be in the ranges of 0.26–0.36, 0.48–0.84 and ∼1 MHz for boron tetrahedral distortion indices of 0.004–0.013, 0.015–0.019 and 0.033, respectively, whereas CQ ∼3.0 MHz corresponds to boron in a triangular site. The obtained numerical relationships make it possible to predict the quadrupole frequencies for these nuclei based only on their local environment, and vice versa, to propose structural models from NMR data. These results provide guidance for studying similar characteristics of other borophosphates, the structure of which varies depending on the initial reaction, composition and temperature. [ABSTRACT FROM AUTHOR]

This paper develops two-filter particle smoothing (TFPS) algorithms for the nonlinear fixed-interval smoothing problem of one generalized hidden Markov model (GHMM), where the current observation depends not only on the current state, but also on one-step previous state. Firstly, by Bayesian approach, the two-filter smoothing (TFS) formula for GHMM is established to calculate smoothing densities. In this TFS formula, the backward information prediction density is generally not a density of the state. This results in a difficulty that the normal sequential Monte Carlo (SMC) sampling technique cannot be directly applied to design corresponding TFPS algorithms based on the TFS formula. To solve this difficulty, a generalized TFS formula for GHMM is then proposed by introducing a sequence of artificial densities. By combining this generalized TFS formula, SMC, and the auxiliary variable sampling technique, a basic auxiliary TFPS (ATFPS) algorithm with quadratic computational complexity is proposed, and a simplified ATFPS algorithm with linear computational complexity is further developed. Finally, the effectiveness and superiority of the two proposed ATFPS algorithms for GHMM are verified via simulation examples and real experimental data. • It studies a generalized HMM where observation depends on two-step states. • Two-filter smoothing formula and its generalization are established. • Auxiliary variable sampling technique is applied to draw samples. • It proposes two particle smoothing algorithms by using sequential Monte Carlo. [ABSTRACT FROM AUTHOR]

The interfacial thermal resistance between adjacent parts is important in the thermal management of micro/nano-scale systems. In this paper, the temperature difference and heat flow methods are adopted to study the interfacial thermal resistance between the smooth surface of metal and the end of carbon nanotube (CNT) by molecular dynamics simulation. The effects of metal type, CNT diameter, and mean interfacial temperature on the interfacial thermal resistance are studied in detail, with the temperature and heat flow conditions applied to the two metal atom groups of a dumbbell-shaped metal–CNT–metal model. For a certain metal type, the diameter and temperature dependences of the interfacial thermal resistance obtained from both the temperature difference and heat flow methods are consistent, the interfacial thermal resistance decreases with increase of CNT diameter exponentially, and the thermal rectification occurs due to different interfacial temperatures. The thermal transfer mechanism at the metal–CNT interface is quantitatively analyzed by calculating the overlap area of the normalized vibrational density of states. The results of this paper will provide in-depth theoretical insights into the heat transfer enhancement at nano-scale interface. [ABSTRACT FROM AUTHOR]