A new set of trial functions for 1s^22sns configurations in a beryllium atom is suggested. A Mathematica program based on the variational method is developed to calculate the wavefunctions and energies of 1s^22sns （n...A new set of trial functions for 1s^22sns configurations in a beryllium atom is suggested. A Mathematica program based on the variational method is developed to calculate the wavefunctions and energies of 1s^22sns （n = 3 - 6） configurations in a beryllium atom. Non-relativistic energy, polarization correction and relativistic correction which include mass correction, one- and two-body Darwin corrections, spin-spin contact interaction and orbit-orbit interaction, are calculated respectively. The results are in good agreement with experimental data.展开更多
In this paper. it is discussed how to constrnct wavefunctions of L-S couplingfermion system, which are classified by group chain A recurrent formula of fractional parentage coefficients with fixedseniority is also g...In this paper. it is discussed how to constrnct wavefunctions of L-S couplingfermion system, which are classified by group chain A recurrent formula of fractional parentage coefficients with fixedseniority is also given.展开更多
The wavefunctions of L-S coupling fermion system, which are classified by group chain U(4ι1 + 4ι2 + 4) Us(2)×(U L(2ι+ 2ι2 + 2) O(2ι1 + 2ι2 + 2) O(2ι+1) ×O(2ι2 + 1) O1 (3)×O2 (3) O(3)), are const...The wavefunctions of L-S coupling fermion system, which are classified by group chain U(4ι1 + 4ι2 + 4) Us(2)×(U L(2ι+ 2ι2 + 2) O(2ι1 + 2ι2 + 2) O(2ι+1) ×O(2ι2 + 1) O1 (3)×O2 (3) O(3)), are constructed through introducing generalized pairs coupled by fermions with different ι. With the help of the fractional parentage coefficients of single-ιfermion system, the author obtains the corresponding fractional parentage coefficients of double-ιfermion system.展开更多
Wavefunction is a fundamental concept of quantum theory.Recent studies have shown surprisingly that wavefunction can be directly reconstructed via the measurement of weak value.The weak value based direct wavefunction...Wavefunction is a fundamental concept of quantum theory.Recent studies have shown surprisingly that wavefunction can be directly reconstructed via the measurement of weak value.The weak value based direct wavefunction reconstruction not only gives the operational meaning of wavefunction,but also provides the possibility of realizing holographic imaging with a totally new quantum approach.Here,we review the basic background knowledge of weak value based direct wavefunction reconstruction combined with recent experimental demonstrations.The main purpose of this work focuses on the idea of holographic imaging via direct wavefunction reconstruction.Since research on this topic is still in its early stage,we hope that this work can attract interest in the field of traditional holographic imaging.In addition,the wavefunction holographic imaging may find important applications in quantum information science.展开更多
By solving rigorously the relativistic wave equations derived from Bargmann–Wigner equation for arbitrary spin, the relativistic wavefunctions in momentum representation for particles with arbitrary spin are deduced.
Discrete Shannon entropy is applied to describe the information in a multiconfiguration Dirac Fock wavefunction. The dependence of Shannon entropy is shown as enlarging the configuration space and it can reach saturat...Discrete Shannon entropy is applied to describe the information in a multiconfiguration Dirac Fock wavefunction. The dependence of Shannon entropy is shown as enlarging the configuration space and it can reach saturation when there are enough configuration state wavefunctions to obtain the convergent energy levels; that is, the calculation procedure in multiconfiguration Dirae Fock method is an entropy saturation process. At the same accuracy level, the basis sets for the smallest entropy are best able to describe the energy state. Additionally, a connection between the sudden change of Shannon information entropies and energy level crossings along with isoelectronic sequence can be set up, which is helpful to find the energy level crossings of interest in interpreting and foreseeing the inversion scheme of energy levels for an x-ray laser.展开更多
We calculate the glueball 〈gg〉 wavefunction and mass in SU(3) Lattice gauge with improved gauge actions on the anisotropic lattice. All simulations are performed on the cluster of our lab. We have measured the scala...We calculate the glueball 〈gg〉 wavefunction and mass in SU(3) Lattice gauge with improved gauge actions on the anisotropic lattice. All simulations are performed on the cluster of our lab. We have measured the scalar and tensor glueball wavefunction. At the same time, we have briefly calculated the glueball mass as for a consistent check.展开更多
Based on atomic crystal configurations,we studied many-body interaction properties of face-centered cubic(fcc)solid argon(Ar)within the atomic distance range of 2.0A to 3.6A at T=300 K.The resulting EOS can accurately...Based on atomic crystal configurations,we studied many-body interaction properties of face-centered cubic(fcc)solid argon(Ar)within the atomic distance range of 2.0A to 3.6A at T=300 K.The resulting EOS can accurately describe the compression behavior of solid Ar under the experimentally investigated pressure range(0~114GPa).Statistically,903(Ar)2 clusters were identified,corresponding to 12 distinct geometric configurations,861(Ar)3 clusters correspond to 25 distinct geometric configurations,816(Ar)4clusters correspond to 27 distinct geometric configurations,and the calculation results exhibited good convergence.For comparative purposes,the EOS of fcc solid Ar was also calculated using a two-body potential-only approach,which showed excellent agreement with experimental data under relevant pressures.Incorporating three-body terms extended the EOS accuracy to 80 GPa,while the inclusion of four-body terms further improved the precision up to 114 GPa.Higher-order many-body terms are expected to enable accurate interpretation of experimental phenomena in solid Ar above 114 GPa.In addition,when the molar volume is reduced to a fixed value,the zero-point vibration pressure has already reached a certain proportion,then it must be considered and cannot be ignored.This study provides a reliable theoretical model for the study of high-pressure properties and zero-point energy of rare gas solids.展开更多
Quantum many-body systems lie at the heart of modern fundamental physics.The study of these systems has revealed a plethora of fascinating phenomena,such as quantum thermalization,many-body localization,and quantum ma...Quantum many-body systems lie at the heart of modern fundamental physics.The study of these systems has revealed a plethora of fascinating phenomena,such as quantum thermalization,many-body localization,and quantum many-body scars.This review provides a comprehensive overview of the recent advances in understanding quantum many-body scars and non-ergodic dynamics in quantum systems on superconducting-circuit platforms,ranging from theoretical mechanisms and effective models to experimental observations.展开更多
Quantum simulation has been developed extensively over the past decades,widely applied to different models to explore dynamics in the quantum regime.Rydberg atoms have strong dipole-dipole interactions and interact wi...Quantum simulation has been developed extensively over the past decades,widely applied to different models to explore dynamics in the quantum regime.Rydberg atoms have strong dipole-dipole interactions and interact with each other over a long distance,which makes it straightforward to build many-body interacting quantum systems to simulate specific models.Additionally,neutral atoms are easily manipulated due to their weak interactions.These advantages make Rydberg many-body system an ideal platform to implement quantum simulations.This paper reviews several quantum simulations for different models based on Rydberg many-body systems,including quantum Ising models in one dimension and two dimensions mainly for quantum magnetism,XY model for excitation transport,SSH model for symmetry-protected topological phases,and critical self-organized behaviors in many-body systems.Besides,some challenges and promising directions of quantum simulations based on Rydberg many-body system are discussed in this paper.展开更多
This article presents an elementary introduction on various aspects of the prototypical integrable model the LiebLiniger Bose gas ranging from the cooperative to the collective features of many-body phenomena. In 1963...This article presents an elementary introduction on various aspects of the prototypical integrable model the LiebLiniger Bose gas ranging from the cooperative to the collective features of many-body phenomena. In 1963, Lieb and Liniger first solved this quantum field theory many-body problem using Bethe＇s hypothesis, i.e., a particular form of wavefunction introduced by Bethe in solving the one-dimensional Heisenberg model in 1931. Despite the Lieb-Liniger model is arguably the simplest exactly solvable model, it exhibits rich quantum many-body physics in terms of the aspects of mathematical integrability and physical universality. Moreover, the Yang-Yang grand canonical ensemble description for the model provides us with a deep understanding of quantum statistics, thermodynamics, and quantum critical phenomena at the many-body physical level. Recently, such fundamental physics of this exactly solved model has been attracting growing interest in experiments. Since 2004, there have been more than 20 experimental papers that rbported novel observations of different physical aspects of the Lieb--Liniger model in the laboratory. So far the observed results are in excellent agreement with results obtained using the analysis of this simplest exactly solved model. Those experimental observations reveal the unique beauty of integrability.展开更多
In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hoppin...In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hopping integrals which are the physical origin of cohesion of atoms. For thesimple case of s-valent system, the inversion of the many-body potentials are discussed in detail by using the lattice inversion method.展开更多
The necessary derivation of negative mass in dispersion dynamics suggests cosmic applications. The method analyzes functional relationships between particle angular frequency, wave vector, rest mass and electromagneti...The necessary derivation of negative mass in dispersion dynamics suggests cosmic applications. The method analyzes functional relationships between particle angular frequency, wave vector, rest mass and electromagnetic or nuclear potential, f(ω, k, m0, V) = 0. A summary of consequential predictions of the dynamics leads to a calculation of ways in which negative mass might influence such phenomena as the rotational velocities that are observed in spiral galaxies. The velocities are found to be not Newtonian in the simple two body approximations for our solar system;but nearly constant with increasing orbital radii. It has moreover been suggested that the motion is due to halo structures of dark matter or dark energy. However, the motion is simply described by many-body gravitation that is transmitted along elastic spiral arms. In this context, we calculate possible effects of negative mass, but without observational confirmation.展开更多
Employing the advanced relativistic configuration interaction(RCI)combined with the many-body perturbation theory(RMBPT)method,we report energies and lifetime values for the lowest 35 energy levels from the(1s^(2))nl ...Employing the advanced relativistic configuration interaction(RCI)combined with the many-body perturbation theory(RMBPT)method,we report energies and lifetime values for the lowest 35 energy levels from the(1s^(2))nl configurations(where the principal quantum number n=2–6 and the angular quantum number l=0,...,n-1)of lithium-like iron Fe XXIV,as well as complete data on the transition wavelengths,radiative rates,absorption oscillator strengths,and line strengths between the levels.Both the allowed(E1)and forbidden(magnetic dipole M1,magnetic quadrupole M2,and electric quadrupole E2)ones are reported.Through detailed comparisons with previous results,we assess the overall accuracies of present RMBPT results to be likely the most precise ones to date.Configuration interaction effects are found to be very important for the energies and radiative properties for the ion.The present RMBPT results are valuable for spectral line identification,plasma modeling,and diagnosing.展开更多
Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this...Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this work,we propose an interaction manybody expansion(IMBE)to calculate the energy of atomic clusters containing covalent bonds.In this approach,the energy of a system is expressed as the sum of the energy of atoms and the interaction energy between the atom and its surrounding atoms.The IMBE method is first applied to calculate the energies of nitrogen clusters,in which the interatomic interactions are truncated to four-body terms.The results show that the IMBE approach could significantly reduce the energy error for nitrogen clusters compared with the traditional MBE method.The weak size and structure dependence of the IMBE error with respect to DFT calculations indicates the IMBE method has good potential application in estimating energy of large covalent systems.展开更多
In this paper the tensor probability current and continuity equation is obtained, with this the correlated cross section of many particle scattering can be evaluation.
We study the charge oscillation in the triangular quantum dots symmetrically coupled to the leads. A strong charge oscillation is observed even for a very small level difference. We attribute this oscillation behaviou...We study the charge oscillation in the triangular quantum dots symmetrically coupled to the leads. A strong charge oscillation is observed even for a very small level difference. We attribute this oscillation behaviour to the many- body effect in the strongly correlated system instead of the physical scenarios based on the mean-field approach in the previous works for the two-level dot. The level difference induces the difference of the occupations between different dots, while the symmetry of the many-body states favours the homogeneous distribution of the charge density on the three dots. The interplay of these two factors results in the charge oscillation.展开更多
In this paper, an extended spectral theorem is given, which enables one to calculate the correlation functions when complex eigenvalues appear. To do so, a Fourier transformation with a complex argument is utilized. W...In this paper, an extended spectral theorem is given, which enables one to calculate the correlation functions when complex eigenvalues appear. To do so, a Fourier transformation with a complex argument is utilized. We treat all the Matsbara frequencies, including Fermionic and Bosonic frequencies, on an equal footing. It is pointed out that when complex eigenvalues appear, the dissipation of a system cannot simply be ascribed to the pure imaginary part of the Green function. Therefore, the use of the name fluctuation-dissipation theorem should be careful.展开更多
Heat and mass transfer during the process of liquid droplet dynamic behaviors has attracted much attention in decades.At mesoscopic scale,numerical simulations of liquid droplets motion,such as impacting,sliding,and c...Heat and mass transfer during the process of liquid droplet dynamic behaviors has attracted much attention in decades.At mesoscopic scale,numerical simulations of liquid droplets motion,such as impacting,sliding,and coalescence,have been widely studied by using the particle-based method named many-body dissipative particle dynamics(MDPD).However,the detailed information on heat transfer needs further description.This paper develops a modified MDPD with energy conservation(MDPDE)by introducing a temperature-dependent long-term attractive interaction.By fitting or deriving the expressions of the strength of the attractive force,the exponent of the weight function in the dissipative force,and the mesoscopic heat friction coefficient about temperature,we calculate the viscosity,self-diffusivity,thermal conductivity,and surface tension,and obtain the Schmidt number Sc,the Prandtl number P r,and the Ohnesorge number Oh for 273 K to 373 K.The simulation data of MDPDE coincide well with the experimental data of water,indicating that our model can be used to simulate the dynamic behaviors of liquid water.Furthermore,we compare the equilibrium contact angle of droplets wetting on solid surfaces with that calculated from three interfacial tensions by MDPDE simulations.The coincident results not only stand for the validation of Young’s equation at mesoscale,but manifest the reliability of our MDPDE model and applicability to the cases with free surfaces.Our model can be extended to study the multiphase flow withcomplex heat and mass transfer.展开更多
基金Project supported by the Scientific Research Foundation for the Returned Overseas Chinese Scholars, Ministry of Education of China (Grant No 2005LXAH06)the Research Foundation of Education Bureau of Anhui Province, China (Grant Nos KJ2008A145 and 2002HBL05)
文摘A new set of trial functions for 1s^22sns configurations in a beryllium atom is suggested. A Mathematica program based on the variational method is developed to calculate the wavefunctions and energies of 1s^22sns （n = 3 - 6） configurations in a beryllium atom. Non-relativistic energy, polarization correction and relativistic correction which include mass correction, one- and two-body Darwin corrections, spin-spin contact interaction and orbit-orbit interaction, are calculated respectively. The results are in good agreement with experimental data.
文摘In this paper. it is discussed how to constrnct wavefunctions of L-S couplingfermion system, which are classified by group chain A recurrent formula of fractional parentage coefficients with fixedseniority is also given.
文摘The wavefunctions of L-S coupling fermion system, which are classified by group chain U(4ι1 + 4ι2 + 4) Us(2)×(U L(2ι+ 2ι2 + 2) O(2ι1 + 2ι2 + 2) O(2ι+1) ×O(2ι2 + 1) O1 (3)×O2 (3) O(3)), are constructed through introducing generalized pairs coupled by fermions with different ι. With the help of the fractional parentage coefficients of single-ιfermion system, the author obtains the corresponding fractional parentage coefficients of double-ιfermion system.
基金supported by the Beijing Academy of Quantum Information Sciencessupported by the National Natural Science Foundation of China(Grant Nos.11674306 and 92065113)the University Synergy Innovation Program of Anhui Province(Grant No.GXXT-2022-039)。
文摘Wavefunction is a fundamental concept of quantum theory.Recent studies have shown surprisingly that wavefunction can be directly reconstructed via the measurement of weak value.The weak value based direct wavefunction reconstruction not only gives the operational meaning of wavefunction,but also provides the possibility of realizing holographic imaging with a totally new quantum approach.Here,we review the basic background knowledge of weak value based direct wavefunction reconstruction combined with recent experimental demonstrations.The main purpose of this work focuses on the idea of holographic imaging via direct wavefunction reconstruction.Since research on this topic is still in its early stage,we hope that this work can attract interest in the field of traditional holographic imaging.In addition,the wavefunction holographic imaging may find important applications in quantum information science.
基金国家自然科学基金，Doctoral Program Founda-tion of Institution of Higher Education of China，国家重点实验室基金，国家重点实验室基金
文摘By solving rigorously the relativistic wave equations derived from Bargmann–Wigner equation for arbitrary spin, the relativistic wavefunctions in momentum representation for particles with arbitrary spin are deduced.
基金the National Natural Science Foundation of China，the Fundamental Research Funds for the Central Universities，the Open Project of Beijing National Laboratory for Molecular Sciences，the Program for Innovative Research Team of Guizhou Province of China，the University Development Fund of Guizhou Province，the Talent Special Fund of Guizhou Province
基金Supported by the National Natural Science Foundation of China under Grant No 11204243the Foundation of Northwest Normal University under Grant No NWNU-LKQN-10-7
文摘Discrete Shannon entropy is applied to describe the information in a multiconfiguration Dirac Fock wavefunction. The dependence of Shannon entropy is shown as enlarging the configuration space and it can reach saturation when there are enough configuration state wavefunctions to obtain the convergent energy levels; that is, the calculation procedure in multiconfiguration Dirae Fock method is an entropy saturation process. At the same accuracy level, the basis sets for the smallest entropy are best able to describe the energy state. Additionally, a connection between the sudden change of Shannon information entropies and energy level crossings along with isoelectronic sequence can be set up, which is helpful to find the energy level crossings of interest in interpreting and foreseeing the inversion scheme of energy levels for an x-ray laser.
文摘We calculate the glueball 〈gg〉 wavefunction and mass in SU(3) Lattice gauge with improved gauge actions on the anisotropic lattice. All simulations are performed on the cluster of our lab. We have measured the scalar and tensor glueball wavefunction. At the same time, we have briefly calculated the glueball mass as for a consistent check.
基金sponsored by the Youth Talent(team)project of Gansu Province(Grant No.2025QNTD12)the Natural ScienceFoundation of Gansu Province(Grant No.25JRRM001,23JRRM0755).
文摘Based on atomic crystal configurations,we studied many-body interaction properties of face-centered cubic(fcc)solid argon(Ar)within the atomic distance range of 2.0A to 3.6A at T=300 K.The resulting EOS can accurately describe the compression behavior of solid Ar under the experimentally investigated pressure range(0~114GPa).Statistically,903(Ar)2 clusters were identified,corresponding to 12 distinct geometric configurations,861(Ar)3 clusters correspond to 25 distinct geometric configurations,816(Ar)4clusters correspond to 27 distinct geometric configurations,and the calculation results exhibited good convergence.For comparative purposes,the EOS of fcc solid Ar was also calculated using a two-body potential-only approach,which showed excellent agreement with experimental data under relevant pressures.Incorporating three-body terms extended the EOS accuracy to 80 GPa,while the inclusion of four-body terms further improved the precision up to 114 GPa.Higher-order many-body terms are expected to enable accurate interpretation of experimental phenomena in solid Ar above 114 GPa.In addition,when the molar volume is reduced to a fixed value,the zero-point vibration pressure has already reached a certain proportion,then it must be considered and cannot be ignored.This study provides a reliable theoretical model for the study of high-pressure properties and zero-point energy of rare gas solids.
基金supported by the Zhejiang Provincial Natural Science Foundation of China(No.LD25A050002)the National Natural Science Foundation of China(No.12375021)the National Key Research and Development Program of China(No.2022YFA1404203).
文摘Quantum many-body systems lie at the heart of modern fundamental physics.The study of these systems has revealed a plethora of fascinating phenomena,such as quantum thermalization,many-body localization,and quantum many-body scars.This review provides a comprehensive overview of the recent advances in understanding quantum many-body scars and non-ergodic dynamics in quantum systems on superconducting-circuit platforms,ranging from theoretical mechanisms and effective models to experimental observations.
文摘Quantum simulation has been developed extensively over the past decades,widely applied to different models to explore dynamics in the quantum regime.Rydberg atoms have strong dipole-dipole interactions and interact with each other over a long distance,which makes it straightforward to build many-body interacting quantum systems to simulate specific models.Additionally,neutral atoms are easily manipulated due to their weak interactions.These advantages make Rydberg many-body system an ideal platform to implement quantum simulations.This paper reviews several quantum simulations for different models based on Rydberg many-body systems,including quantum Ising models in one dimension and two dimensions mainly for quantum magnetism,XY model for excitation transport,SSH model for symmetry-protected topological phases,and critical self-organized behaviors in many-body systems.Besides,some challenges and promising directions of quantum simulations based on Rydberg many-body system are discussed in this paper.
基金supported by the National Basic Research Program of China(Grant No.2012CB922101)the National Natural Science Foundation of China(Grant Nos.11374331 and 11304357)
文摘This article presents an elementary introduction on various aspects of the prototypical integrable model the LiebLiniger Bose gas ranging from the cooperative to the collective features of many-body phenomena. In 1963, Lieb and Liniger first solved this quantum field theory many-body problem using Bethe＇s hypothesis, i.e., a particular form of wavefunction introduced by Bethe in solving the one-dimensional Heisenberg model in 1931. Despite the Lieb-Liniger model is arguably the simplest exactly solvable model, it exhibits rich quantum many-body physics in terms of the aspects of mathematical integrability and physical universality. Moreover, the Yang-Yang grand canonical ensemble description for the model provides us with a deep understanding of quantum statistics, thermodynamics, and quantum critical phenomena at the many-body physical level. Recently, such fundamental physics of this exactly solved model has been attracting growing interest in experiments. Since 2004, there have been more than 20 experimental papers that rbported novel observations of different physical aspects of the Lieb--Liniger model in the laboratory. So far the observed results are in excellent agreement with results obtained using the analysis of this simplest exactly solved model. Those experimental observations reveal the unique beauty of integrability.
文摘In this paper, we deduce the analytical form of many-body interatomic potentials based on the Green's function in tight-binding representation. The many-body potentials are expressed as the functions of the hopping integrals which are the physical origin of cohesion of atoms. For thesimple case of s-valent system, the inversion of the many-body potentials are discussed in detail by using the lattice inversion method.
文摘The necessary derivation of negative mass in dispersion dynamics suggests cosmic applications. The method analyzes functional relationships between particle angular frequency, wave vector, rest mass and electromagnetic or nuclear potential, f(ω, k, m0, V) = 0. A summary of consequential predictions of the dynamics leads to a calculation of ways in which negative mass might influence such phenomena as the rotational velocities that are observed in spiral galaxies. The velocities are found to be not Newtonian in the simple two body approximations for our solar system;but nearly constant with increasing orbital radii. It has moreover been suggested that the motion is due to halo structures of dark matter or dark energy. However, the motion is simply described by many-body gravitation that is transmitted along elastic spiral arms. In this context, we calculate possible effects of negative mass, but without observational confirmation.
基金Project supported by the Research Foundation for Higher Level Talents of West Anhui University(Grant No.WGKQ2021005)。
文摘Employing the advanced relativistic configuration interaction(RCI)combined with the many-body perturbation theory(RMBPT)method,we report energies and lifetime values for the lowest 35 energy levels from the(1s^(2))nl configurations(where the principal quantum number n=2–6 and the angular quantum number l=0,...,n-1)of lithium-like iron Fe XXIV,as well as complete data on the transition wavelengths,radiative rates,absorption oscillator strengths,and line strengths between the levels.Both the allowed(E1)and forbidden(magnetic dipole M1,magnetic quadrupole M2,and electric quadrupole E2)ones are reported.Through detailed comparisons with previous results,we assess the overall accuracies of present RMBPT results to be likely the most precise ones to date.Configuration interaction effects are found to be very important for the energies and radiative properties for the ion.The present RMBPT results are valuable for spectral line identification,plasma modeling,and diagnosing.
基金supported by the National Natural Science Foundation of China(No.21773297,No.21973108,and No.21921004)supported by the National Natural Science Foundation of China(No.21805258)supported by the National Natural Science Foundation of China(No.21973107)。
文摘Although the many-body expansion(MBE)approach is widely applied to estimate the energy of large systems containing weak interactions,it is inapplicable to calculating the energies of covalent or metal clusters.In this work,we propose an interaction manybody expansion(IMBE)to calculate the energy of atomic clusters containing covalent bonds.In this approach,the energy of a system is expressed as the sum of the energy of atoms and the interaction energy between the atom and its surrounding atoms.The IMBE method is first applied to calculate the energies of nitrogen clusters,in which the interatomic interactions are truncated to four-body terms.The results show that the IMBE approach could significantly reduce the energy error for nitrogen clusters compared with the traditional MBE method.The weak size and structure dependence of the IMBE error with respect to DFT calculations indicates the IMBE method has good potential application in estimating energy of large covalent systems.
文摘In this paper the tensor probability current and continuity equation is obtained, with this the correlated cross section of many particle scattering can be evaluation.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 11174228 and 10874132)
文摘We study the charge oscillation in the triangular quantum dots symmetrically coupled to the leads. A strong charge oscillation is observed even for a very small level difference. We attribute this oscillation behaviour to the many- body effect in the strongly correlated system instead of the physical scenarios based on the mean-field approach in the previous works for the two-level dot. The level difference induces the difference of the occupations between different dots, while the symmetry of the many-body states favours the homogeneous distribution of the charge density on the three dots. The interplay of these two factors results in the charge oscillation.
文摘In this paper, an extended spectral theorem is given, which enables one to calculate the correlation functions when complex eigenvalues appear. To do so, a Fourier transformation with a complex argument is utilized. We treat all the Matsbara frequencies, including Fermionic and Bosonic frequencies, on an equal footing. It is pointed out that when complex eigenvalues appear, the dissipation of a system cannot simply be ascribed to the pure imaginary part of the Green function. Therefore, the use of the name fluctuation-dissipation theorem should be careful.
基金Project supported by the National Natural Science Foundation of China(Nos.11872283,12002242,11902188,and 12102218)the Shanghai Science and Technology Talent Program(No.19YF1417400)the China Postdoctoral Science Foundation(No.2020M680525)。
文摘Heat and mass transfer during the process of liquid droplet dynamic behaviors has attracted much attention in decades.At mesoscopic scale,numerical simulations of liquid droplets motion,such as impacting,sliding,and coalescence,have been widely studied by using the particle-based method named many-body dissipative particle dynamics(MDPD).However,the detailed information on heat transfer needs further description.This paper develops a modified MDPD with energy conservation(MDPDE)by introducing a temperature-dependent long-term attractive interaction.By fitting or deriving the expressions of the strength of the attractive force,the exponent of the weight function in the dissipative force,and the mesoscopic heat friction coefficient about temperature,we calculate the viscosity,self-diffusivity,thermal conductivity,and surface tension,and obtain the Schmidt number Sc,the Prandtl number P r,and the Ohnesorge number Oh for 273 K to 373 K.The simulation data of MDPDE coincide well with the experimental data of water,indicating that our model can be used to simulate the dynamic behaviors of liquid water.Furthermore,we compare the equilibrium contact angle of droplets wetting on solid surfaces with that calculated from three interfacial tensions by MDPDE simulations.The coincident results not only stand for the validation of Young’s equation at mesoscale,but manifest the reliability of our MDPDE model and applicability to the cases with free surfaces.Our model can be extended to study the multiphase flow withcomplex heat and mass transfer.
