An accurate analytical surface potential model of heterojunction tunnel FET

Based on the accurate and efficient thermal injection method, we develop a fully analytical surface potential model for the heterojunction tunnel field-effect transistor(H-TFET). This model accounts for both the effects of source depletion and inversion charge, which are the key factors influencing the charge, capacitance and current in H-TFET. The accuracy of the model is validated against TCAD simulation and is greatly improved in comparison with the conventional model based on Maxwell–Boltzmann approximation. Furthermore, the dependences of the surface potential and electric field on biases are well predicted and thoroughly analyzed.

A Fully Flexible Potential Model for Carbon Dioxide

A fully flexible potential model for carbon dioxide has been developed to predict the vapor-liquid coexistence properties using the NVT-Gibbs ensemble Monte Carlo technique(GEMC).The average absolute deviation between our simulation and the literature experimental data for saturated liquid and vapor densities is 0.3% and 2.0%,respectively.Compared with the experimental data,our calculated results of critical properties(7.39 MPa,304.04 K,and 0.4679 g?cm-3) are acceptable and are better than those from the rescaling the potential parameters of elementary physical model(EPM2).The agreement of our simulated densities of supercritical carbon dioxide with the experimental data is acceptable in a wide range of pressure and temperature.The radial distribution function estimated at the supercritical conditions suggests that the carbon dioxide is a nonlinear molecule with the C O bond length of 0.117 nm and the O C O bond angle of 176.4°,which are consistent with Car-Parrinello molecular-dynamics(CPMD),whereas the EPM2 model shows large deviation at supercritical state.The predicted self-diffusion coefficients are in agreement with the experiments.

A Potential Model for Cylindrical Pores

An analytical potential for cylindrical pores has been derived by introducing a variational method into the integration for the calculation of the interaction energy between the wall molecules and a test molecule, all of which are represented by Lennard-Jones potential. The model proposed gives good fit to the results from the cylindrical surface model and the pseudoatom model. To test the potential proposed rigorously, we have carried out grand canonical ensemble Monte Carlo(GCMC) simulation of nitrogen in the MCM-41 pore at 77 K, and compared the simulated adsorption isotherm with the experimental data reported in the literature. The simulated isotherm from our model is in almost qualitative agreement with experiment. Consequently, the model proposed provides an explicit and accurate description of cylindrical pores represented by the Lennard-Jones potential. Moreover, the model can be easily applied to a variety of cylindrical pores, ranging from cylindrical surface to finite thickness walls, in both theoretical studies and computer simulations.

πN Elastic Scattering and Resonances in Quark Potential Model

The quark potential model is used to investigate the low-energy elastic scattering of πN system. The model potential consists of the t-channel and s-channel one-gluon exchange potentials and the harmonic oscillator confining potential. By means of the resonating group method, a nonlocal effective potential for the πN system is derived from the interquark potentials and used to calculate the πN elastic scattering phase shifts. By considering the effect of QCD renormalization, the suppression of the spin-orbital coupling and the contribution of the color octet of the clusters （qq） and （qqq）, the numerical results are in fairly good agreement with the experimental data. The same model and method are employed to investigate the possible πN resonances. For this purpose, the resonating group equation is transformed into a standard Schrodinger equation in which the nonlocal effective πN interaction potential is included. Solving the Schrodinger equation by the variational method, we are able to reproduce the masses of some currently concerned πN resonances.

Two-colour coherent control of multiphoton ionization： a comparison between long-range and short-range potential model atoms

Using the numerical solution of the time-dependent SchrSdinger equation of a one-dimensional model atom in a two-colour laser field, we have investigated the effects of the potential models on coherent control of atomic multiphoton ionization. It is found that the photoelectron spectra are obviously different for the long-range （Coulomb-like） and short-range （with no excited bound states） potential model atoms, which are produced by two-colour coherent control of atomic multiphoton ionization in a few laser cycles. Our results indicate that two-colour coherent control of atomic multiphoton ionization can be observed in simulations, depending on the choice of the model potentials.

Theoretical uncertainties of(d,^(3)He)and(^(3)He,d)reactions owing to the uncertainties of optical model potentials

The theoretical uncertainties of single proton transfer cross sections of the(^(3)He,d)and(d,^(3)He)reactions,owing to the uncertainties of the entrance-and exit-channel optical model potentials,are examined with the^(30)Si(^(3)He,d)^(31)P,^(13)B(d,^(3)He)^(12)Be,and^(34)S(^(3)He,d)^(35)Cl reactions at incident energies of 25,46,and 25 MeV,respectively,within the framework of the distorted wave Born approximation.The differential cross sections at the first peaks in the angular distributions of these reactions are found to have uncertainties of approximately 5%,owing to the uncertainties in the optical model potentials from 20,000 calculations of randomly sampled parameters.This amount of uncertainty is found to be nearly independent of the angular momentum transfer and the target masses within the studied range of incident energies.Uncertainties in the single proton spectroscopic factors obtained by matching the theoretical and experimental cross sections at different scattering angles are also discussed.

Application of a microscopic optical potential of chiral effective field theory in (p, d) transfer reactions

The microscopic global nucleon–nucleus optical model potential(OMP)proposed by Whitehead,Lim,and Holt,the WLH potential(Whitehead et al.,Phys Rev Lett 127:182502,2021),which was constructed in the framework of many-body per-turbation theory with state-of-the-art nuclear interactions from chiral effective field theory(EFT),was tested with(p,d)transfer reactions calculated using adiabatic wave approximation.The target nuclei included both stable and unstable nuclei,and the incident energies reached 200 MeV.The results were compared with experimental data and predictions using the phenomenological global optical potential of Koning and Delaroche,the KD02 potential.Overall,we found that the micro-scopic WLH potential described the(p,d)reaction angular distributions similarly to the phenomenological KD02 potential;however,the former was slightly better than the latter for radioactive targets.On average,the obtained spectroscopic factors(SFs)using both microscopic and phenomenological potentials were similar when the incident energies were below approxi-mately 120 MeV.However,their difference tended to increase at higher incident energies,which was particularly apparent for the doubly magic target nucleus 40Ca.

Bottomonium states versus recent experimental observations in the QCD-inspired potential model

In the QCD-inspired potential model where the quark-antiquark interaction consists of the usual one- gluon-exchange and the mixture of long-range scalar and vector linear confining potentials with the lowest order relativistic correction, we investigate the mass spectra and electromagnetic processes of a bottomonium system by using the Gaussian expansion method. It reveals that the vector component of the mixing confinement is anticonfining and takes around 18.51% of the confining potential. Combining the new experimental data released by Belle, BaBar and LHC, we systematically discuss the energy levels of the bottomouium states and make the predictions of the electromagnetic decays for further experiments.

Two-proton radioactivity within Coulomb and proximity potential model

Considering the preformation probability of the two emitted protons in the parent nucleus,we extend the Coulomb and proximity potential model(CPPM)to systematically study two-proton(2p)radioactivity half-lives of the nuclei close to proton drip line.The proximity potential chosen is Prox.81 proposed by Blocki et al.in 1981.Furthermore,we apply this model to predict the half-lives of possible 2p radioactive candidates whose 2p radioactivity is energetically allowed or observed but not yet quantified in the evaluated nuclear properties table NUBASE2016.The predicted results are in good agreement with those from other theoretical models and empirical formulas,namely the effective liquid drop model(ELDM),generalized liquid drop model(GLDM),Gamow-like model,Sreeja formula and Liu formula.

An Equation of State for Fluids by Applying the Tower-Well Potential Model

A simple theoretical equation of state is derived by applying the Tower-Well potential model about the molecular distribution based on the generalized van der Waals partition function. It needs only three molecular parameters which have distinct physical meanings. The resulting equation of state predicts rather well the Vapor pressures, saturate liquid volumes, saturated vapor volumes and PVT thermodynamic properties of polar and structurally complex molecules over a wide temperature and pressure range.

Structure and Properties of Hydrotalcite Using Electrostatic Potential Energy Model

The electrostatic potential energy model of hydrotalcites was based on the theory of crystallography. The anionic potential energy of MgAl-hydrotalcites, with 20 layers and 2107 anions per layer, was calculated, and the anionic stability of the hydrotalcites was investigated. The charge density of the layer and the distance between the adjacent anions varied with the molar ratio of Al^3＋/（Mg^2＋ ＋ Al^3＋）. Anionic potential energy depended on the charge and size of the anions. Calculation results remained consistent with thermal stability and the ion exchange ability reported. This model is able to predict anionic stability of the hydrotalcites.

Comparison of Ten Potential Evapotranspiration Models and Their Attribution Analyses for Ten Chinese Drainage Basins

Potential evapotranspiration(EPET)is usually calculated by empirical methods from surface meteorological variables,such as temperature,radiation and wind speed.The in-situ measured pan evaporation(ETpan)can also be used as a proxy for EPET.In this study,EPET values computed from ten models are compared with observed ETpan data in ten Chinese river basins for the period 1961−2013.The daily observed meteorological variables at 2267 stations are used as the input to those models,and a ranking scheme is applied to rank the statistical quantities(ratio of standard deviations,correlation coefficient,and ratio of trends)between ETpan and modeled EPET in different river basins.There are large deviations between the modeled EPET and the ETpan in both the magnitude and the annual trend at most stations.In eight of the basins(except for Southeast and Southwest China),ETpan shows decreasing trends with magnitudes ranging between−0.01 mm d−1 yr−1 and−0.03 mm d−1 yr−1,while the decreasing trends in modeled EPET are less than−0.01 mm d−1 yr−1.Inter comparisons among different models in different river basins suggest that PETHam1 is the best model in the Pearl River basin,PETHam2 outperforms other models in the Huaihe River,Yangtze River and Yellow River basins,and PETFAO is the best model for the remaining basins.Sensitivity analyses reveal that wind speed and sunshine duration are two important factors for decreasing EPET in most basins except in Southeast and Southwest China.The increasing EPET trend in Southeast China is mainly attributed to the reduced relative humidity.

Molecular properties and potential energy function model of BH under external electric field

Using the density functional B3P86/cc-PV5Z method, the geometric structure of BH molecule under different external electric fields is optimized, and the bond lengths, dipole moments, vibration frequencies, and other physical properties parameters are obtained. On the basis of setting appropriate parameters, scanning single point energies are obtained by the same method and the potential energy curves under different external fields are also obtained. These results show that the physical property parameters and potential energy curves may change with external electric field, especially in the case of reverse direction electric field. The potential energy function without external electric field is fitted by Morse potential, and the fitting parameters are obtained which are in good agreement with experimental values. In order to obtain the critical dissociation electric parameter, the dipole approximation is adopted to construct a potential model fitting the corresponding potential energy curve of the external electric field. It is found that the fitted critical dissociation electric parameter is consistent with numerical calculation, so that the constructed model is reliable and accurate. These results will provide important theoretical and experimental reference for further studying the molecular spectrum, dynamics, and molecular cooling with Stark effect.

Numerical verification of similar Cam-clay model based on generalized potential theory

From the mathematical principles, the generalized potential theory can be employed to create constitutive model of geomaterial directly. The similar Cam-clay model, which is created based on the generalized potential theory, has less assumptions,clearer mathematical basis, and better computational accuracy. Theoretically, it is more scientific than the traditional Cam-clay models. The particle flow code PFC3 D was used to make numerical tests to verify the rationality and practicality of the similar Cam-clay model. The verification process was as follows: 1) creating the soil sample for numerical test in PFC3 D, and then simulating the conventional triaxial compression test, isotropic compression test, and isotropic unloading test by PFC3D; 2)determining the parameters of the similar Cam-clay model from the results of above tests; 3) predicting the sample's behavior in triaxial tests under different stress paths by the similar Cam-clay model, and comparing the predicting results with predictions by the Cam-clay model and the modified Cam-clay model. The analysis results show that the similar Cam-clay model has relatively high prediction accuracy, as well as good practical value.

The Nucleon-Actinide Global Optical Model Potential Below 300 MeV

A set of new global phenomenological optical model potential parameters has been obtained in the mass range of target nuclei 220≤A≤260 with incident energies below 300 MeV, by simultaneously fitting the experimental data of 232Th and 23Su, and these potential parameters are analyzed and used to calculate the reaction cross sections, energy spectra and double differ- ential cross sections for p＋232Th reaction. Comparison of calculated results using these potential parameters with available experimental data shows that the present form of global optical model potential could reproduce experimental data for both the neutron and the proton.

Astrophysical S-factor and reaction rate for 15N(p,γ)16O within the modified potential cluster model

We study radiative p^(15)N capture on the ground state of ^(16)O at stellar energies within the framework of a modified potential cluster model(MPCM)with forbidden states,including low-lying resonances.The investigation of the ^(15)N(p,γ0)^(16)O reaction includes the consideration of ^(3)S_(1) resonances due to E1 transitions and the contribution of the ^(3)P_(1) scattering wave in the p+^(15)N channel due to the ^(3)P_(1)→^(3)P_(0)M1 transition.We calculated the astrophysical low-energy S-factor,and the extrapolated S(0)turned out to be within 34.7−40.4 keV·b.The important role of the asymptotic constant(AC)for the ^(15)N(p,γ0)16O process with interfering ^(3)S_(1)(312)and ^(3)S_(1)(962)resonances is elucidated.A comparison of our calculation for the S-factor with existing experimental and theoretical data is addressed,and a reasonable agreement is found.The reaction rate is calculated and compared with the existing rates.It has negligible dependence on the variation of AC but shows a strong impact of the interference of ^(3)S_(1)(312)and ^(3)S_(1)(962)resonances in reference to the CNO Gamow windows,especially at low temperatures.We estimate the contribution of cascade transitions to the reaction rate based on the exclusive experimental data from Phys.Rev.C.85,065810(2012).The reaction rate enhancement due to the cascade transitions is observed from T_(9)>0.3 and reaches the maximum factor~1.3 at T_(9)=1.3.We present the Gamow energy window and a comparison of rates for radiative proton capture reactions ^(12)N(p,γ)^(13)O,^(13)N(p,γ)^(14)O,^(14)N(p,γ)^(15)O,and ^(15)N(p,γ)^(16)O obtained in the framework of the MPCM and provide the temperature windows,prevalence,and significance of each process.

Systematic investigation of nucleon optical model potentials in(p,d)transfer reactions

The consistent three-body model reaction methodology(TBMRM)proposed by J.Lee et al.[Phys.Rev.C 69,064313(2004);Phys.Rev.C 73,044608(2006);Phys.Rev.C 75,064320(2007)],which includes adopting the simple zero-range adiabatic wave approximation,constraining the single-particle potentials using modern Hartree-Fock calculations,and using global nucleon optical model potential(OMP)geometries,are widely applied in systematic studies of transfer reactions.In this study,we investigate the influence of different nucleon OMPs in extracting spectroscopic factors(SFs)from(p,d)reactions.Our study covers 32 sets of angular distribution data of(p,d)reactions on four targets and a large range of incident energies(20-200 MeV/nucleon).This study uses two semi-microscopic nucleon OMPs,i.e.,Jeukenne,Lejeune,and Mahaux(JLM)[Phys.Rev.C 16,80(1977);Phys.Rev.C 58,1118(1998)]and CTOM[Phys.Rev.C 94,034606(2016)],and a pure microscopic nucleon potential,i.e.,WLH[Phys.Rev.Lett.127,182502(2021)].The results are compared with those using the phenomenological global optical potential KD02[Nucl.Phys.A 713,231(2003)].We find that the incident energy dependence of spectroscopic factors extracted from(p,d)reactions is evidently suppressed when microscopic OMPs are employed for ^(12)C,^(28)Si,and 40Ca.In addition,spectroscopic factors extracted using the systematic microscopic optical potential CTOM based on the Dirac-Brueckner-Hartree-Fock theory are more in line with the results obtained from(e,e′p)measurements,except for 16O and ^(40)Ca at high energies(>100 MeV),necessitating an exact treatment of double-magic nuclei.The results obtained by using the pure microscopic optical potential,WLH,based on the EFT theory show the same trend as those of CTOM but are generally higher.The JLM potential,which relies on simplified nuclear matter calculations with old-fashioned bare interactions,produces results that are very similar to those of the phenomenological potential KD02.Our results indicate that modern microscopic OMPs are reliable tools for probing the nuclear structure using transfer reactions across a wide energy range.

Al-doping influence on crystal growth of Ni–Al alloy: Experimental testing of a theoretical model

Recently, a condensing potential model was developed to evaluate the crystallization ability of bulk materials [Ye X X, Ming C, Hu Y C and Ning X J 2009 J. Chem. Phys. 130 164711 and Peng K, Ming C, Ye X X, Zhang W X, Zhuang J and Ning X J 2011 Chem. Phys. Lett. 501 330], showing that the best temperature for single crystal growth is about0.6Tm, where Tm is the melting temperature, and for Ni–Al alloy, more than 6 wt% of Al-doping will badly reduce the crystallization ability. In order to verify these predictions, we fabricated Ni–Al films with different concentrations of Al on Si substrates at room temperature by pulsed laser deposition, and post-annealed the films at 833, 933, 1033（- 0.6Tm）,1133, and 1233 K in vacuum furnace, respectively. The x-ray diffraction spectra show that annealing at 0.6Tm is indeed best for larger crystal grain formation, and the film crystallization ability remarkably declines with more than 6-wt% Al doping.

Recursion-transform method and potential formulae of the m×n cobweb and fan networks

In this paper, we made a new breakthrough, which proposes a new recursion–transform（RT） method with potential parameters to evaluate the nodal potential in arbitrary resistor networks. For the first time, we found the exact potential formulae of arbitrary m × n cobweb and fan networks by the RT method, and the potential formulae of infinite and semi-infinite networks are derived. As applications, a series of interesting corollaries of potential formulae are given by using the general formula, the equivalent resistance formula is deduced by using the potential formula, and we find a new trigonometric identity by comparing two equivalence results with different forms.

Numerical modeling and dynamic analysis of the 2017 Xinmo landslide in Maoxian County, China

A catastrophic landslide occurred at Xinmo village in Maoxian County, Sichuan Province,China, on June 24, 2017. A 2.87×106 m3 rock mass collapsed and entrained the surface soil layer along the landslide path. Eighty-three people were killed or went missing and more than 103 houses were destroyed. In this paper, the geological conditions of the landslide are analyzed via field investigation and high-resolution imagery. The dynamic process and runout characteristics of the landslide are numerically analyzed using a depth-integrated continuum method and Mac Cormack-TVD finite difference algorithm.Computational results show that the evaluated area of the danger zone matchs well with the results of field investigation. It is worth noting that soil sprayed by the high-speed blast needs to be taken into account for such kind of large high-locality landslide. The maximum velocity is about 55 m/s, which is consistent with most cases. In addition, the potential danger zone of an unstable block is evaluated. The potential risk area evaluated by the efficient depthintegrated continuum method could play a significant role in disaster prevention and secondary hazard avoidance during rescue operations.