We present a formalism of charge self-consistent dynamical mean field theory(DMFT)in combination with densityfunctional theory(DFT)within the linear combination of numerical atomic orbitals(LCNAO)framework.We implemen...We present a formalism of charge self-consistent dynamical mean field theory(DMFT)in combination with densityfunctional theory(DFT)within the linear combination of numerical atomic orbitals(LCNAO)framework.We implementedthe charge self-consistent DFT+DMFT formalism by interfacing a full-potential all-electron DFT code with threehybridization expansion-based continuous-time quantum Monte Carlo impurity solvers.The benchmarks on several 3d,4fand 5f strongly correlated electron systems validated our formalism and implementation.Furthermore,within the LCANOframework,our formalism is general and the code architecture is extensible,so it can work as a bridge merging differentLCNAO DFT packages and impurity solvers to do charge self-consistent DFT+DMFT calculations.展开更多
Established on the framework of Frege's philosophy of language, with the help of Tarlski in the development on the innovation oftheory of truth (including methodology level), Davidson explained the concept of mean...Established on the framework of Frege's philosophy of language, with the help of Tarlski in the development on the innovation oftheory of truth (including methodology level), Davidson explained the concept of meaning in the process of language Ibrmation with the interpretation and characterization of"the formalization of axis" which was Developing from "t refers to x" to "s means m ", then to" s means that p", then to " (T) s is T if and only ifp". After a series of ideas conversion on the restructuring and improvement, Davidson finally created an innovative view of meaning on the holistic level. In order to realize the meaning of language itself as the axis, with Tarski's theory of truth as the transmission fulcrum, with natural language translation and interpretation as the actual operation range, he has run the theory of meaning as the understanding, interpretation and action picture of people dealing with events arranged in a crisscross pattern world.展开更多
A combination of the iterative perturbation theory (ITP) of the dynamical mean field theory (DMFT) and coherentpotential approximation (CPA) is generalized to the double exchange model with orbital degeneracy. T...A combination of the iterative perturbation theory (ITP) of the dynamical mean field theory (DMFT) and coherentpotential approximation (CPA) is generalized to the double exchange model with orbital degeneracy. The Hubbard interaction and the off-diagonal components for the hopping matrix tij^mn(m ≠ n) are considered in our calculation of spectrum and optical conductivity. The numerical results show that the effects of the non-diagonal hopping matrix elements are important.展开更多
In order to understand the electric interfacial behavior, mean field based electric double layer (EDL) theory has been continuously developed over the past 150 years. In this article, we briefly review the developme...In order to understand the electric interfacial behavior, mean field based electric double layer (EDL) theory has been continuously developed over the past 150 years. In this article, we briefly review the development of the EDL model, from the dimensionless Gouy-Chapman model to the symmetric Bikerman-Freise model, and finally toward size-asymmetric mean field theory models. We provide the general derivations within the framework of Helmholtz free energy of the lattice- gas model, and it can be seen that the above-mentioned models are consistent in the sense that the interconversi0n among them can be achieved by reducing the basic assumptions.展开更多
We investigate the effect of interaction, temperature, and anisotropic parameter on the quantum phase transitions in an anisotropic square-octagon lattice with fermions under the framework of the single band Hubbard m...We investigate the effect of interaction, temperature, and anisotropic parameter on the quantum phase transitions in an anisotropic square-octagon lattice with fermions under the framework of the single band Hubbard model through using the combination of cellular dynamical mean field theory and a continuous time Monte Carlo algorithm. The competition between interaction and temperature shows that with the increase of the anisotropic parameter, the critical on-site repulsive interaction for the metal-insulator transition increases for fixed temperature. The interaction-anisotropic parameter phase diagram reveals that with the decrease of temperature, the critical anisotropic parameter for the Mott transition will increase for fixed interaction cases.展开更多
We propose a quantization procedure for the nucleon-scMar meson system, in which an arbitrary mean scalar meson field Ф is introduced. The equivalence of this procedure with the usual one is proven for any given valu...We propose a quantization procedure for the nucleon-scMar meson system, in which an arbitrary mean scalar meson field Ф is introduced. The equivalence of this procedure with the usual one is proven for any given value of qS. By use of this procedure, the scalar meson field in the Walecka's MFA and in Chin's RHA are quantized around the mean field, Its corrections on these theories are considered by perturbation up to the second order. The arbitrariness of Ф makes us free to fix it at any stage in the calculation. When we fix it in the way of Walecka's MFA, the quantum corrections are big, and the result does not converge. When we fix it in the way of Chin's RHA, the quantum correction is negligibly small, and the convergence is excellent. It shows that RHA covers the leading part of quantum field theory for nuclear systems and is an excellent zeroth order approximation for further quantum corrections, while the Walecka's MFA does not. We suggest to fix the parameter Ф at the end of the whole calculation by minimizing the total energy per-nucleon for the nuclear matter or the total energy for the finite nucleus, to make the quantized relativistic mean field theory (QRMFT) a variational method.展开更多
The newly synthesized element 117 and its alpha-decay chains are systematically investigated in the framework of the relativistic mean field theory with parameter sets NL-Z2 and TMA. The ground-state properties of the...The newly synthesized element 117 and its alpha-decay chains are systematically investigated in the framework of the relativistic mean field theory with parameter sets NL-Z2 and TMA. The ground-state properties of the superheavy nuclei on the alpha-decay chains of 294 117 and 293 117 are calculated. The experimental alpha-decay energies and ha Jr-lives of the two alpha-decay chains are reasonably reproduced by the model The detailed discussions on the binding energies, alpha-decay energies, half-lives, quadrupole deformations, potential energy curves, and single particle levels of the two alpha-decay chains are made.展开更多
This paper proposes an impurity solver for the dynamical mean field theory (DMFT) study of the Mott insulators, which is based on the second order perturbation of the hybridization function. After careful benchmarki...This paper proposes an impurity solver for the dynamical mean field theory (DMFT) study of the Mott insulators, which is based on the second order perturbation of the hybridization function. After careful benchmarking with quantum Monte Carlo results on the anti-ferromagnetic phase of the Hubbard model, it concludes that this impurity solver can capture the main physical features in the strong coupling regime and can be a very useful tool for the LDA (local density approximation) + DMFT studies of the Mort insulators with long range order.展开更多
The nuclei around magic number N=126 are investigated in the deformed relativistic mean field (RMF)model with effective interactions TMA.We focus investigations on the N=126 isotonic chain.The N=126 shellevolution is ...The nuclei around magic number N=126 are investigated in the deformed relativistic mean field (RMF)model with effective interactions TMA.We focus investigations on the N=126 isotonic chain.The N=126 shellevolution is studied by analyzing the variations of two-neutron (proton) separation energies,quadruple deformations,single particle levels etc.The good agreement of two-neutron separation energies between experimental data and calculatedvalues is reached.The RMF theory predicts that the sizes of N=126 shell become smaller and smaller withthe increasing of proton number Z.However,the N=126 shell exists in our calculated region all along.According tothe calculated two-proton separation energies,the RMF theory suggests ^(220)Pu is a two-proton drip-line nucleus in theN=126 isotonic chain.展开更多
Phase diagram and thermodynamic parameters of the random field Ising model (RFIM) on spherical lattice are studied by using mean field theory. This lattice is placed in an external magnetic field (B). The random f...Phase diagram and thermodynamic parameters of the random field Ising model (RFIM) on spherical lattice are studied by using mean field theory. This lattice is placed in an external magnetic field (B). The random field (hi) is assumed to be Gaussian distributed with zero mean and a variance (hi2) = HRF2. The free energy (F), the magnetization (M) and the order parameter (q) are calculated. The ferromagnetic (FM) spin-glass (SG) phase transition is clearly observed. The critical temperature (Tc) is computed under a critical intensity of random field HRF = V/2/πJ. The phase transition from FM to paramagnetic (PM) occurs at TC = J/k in the absence of magnetic field. The critical temperature decreases as HRF increases in the phase boundary of FM-to-SG. The magnetic susceptibility (X) shows a sharp cusp at TC and the specific heat (C) has a singularity in small random field. The internal energy (U) has a similar behaviour to that obtained from the Monte Carlo simulation.展开更多
Relativistic mean-field theory and phase-shift analysis are combined together to investigate the elasticCoulomb scattering between electrons and unstable nuclei.Electron scattering at several different energies is stu...Relativistic mean-field theory and phase-shift analysis are combined together to investigate the elasticCoulomb scattering between electrons and unstable nuclei.Electron scattering at several different energies is studiedand compared,in order to see the energy dependence of electron-nucleus scattering.It is shown that electron scattering at200 MeV or 300 MeV can be used to reveal electron-nucleus scattering information around the first diffraction minimum-Shiftsin opposite directions are obtained for the first diffraction minima of the electron scattering off the ground andfirst excited states of ^(17)F with ^(16)O as reference,and similar effects are obtained for ^(18)Ne.Besides,some neutron-richN = 8 isotones are also studied.Results show that electron scattering will be very useful and important in studyingboth proton- and neutron-rich nuclei in the future.展开更多
In this work, the ground-state properties of Pt, Hg, Pb, and Po isotopes have been systematically investigated in the deformed relativistic mean field (RMF) theory with the new parameter set FSUGold. The calculated ...In this work, the ground-state properties of Pt, Hg, Pb, and Po isotopes have been systematically investigated in the deformed relativistic mean field (RMF) theory with the new parameter set FSUGold. The calculated results show that FSUGold is as successful as NL3 in reproducing the ground-state binding energies of the nuclei in this region. The calculated two- neutron separation energies, quadrupole deformations, and root-mean-square charge radii are in agreement with the experimental data. The parameter set FSUGold can successfully describe the shell effect of the neutron magic number N = 126 and give smaller neutron skin thicknesses than NL3 for all the nuclei considered.展开更多
In the mean-field theory of atom-molecule systems, where the bosonic atoms combine to form molecules, there is no usual U(1) symmetry, which presents an apparent hurdle for calculating the Berry connection in these ...In the mean-field theory of atom-molecule systems, where the bosonic atoms combine to form molecules, there is no usual U(1) symmetry, which presents an apparent hurdle for calculating the Berry connection in these systems. We develop a perturbation expansion method of Hannay's angle suitable for calculating the Berry curvature in the atom- molecule systems. With this Berry curvature, the Berry connection can be computed naturally. We use a three-level atom-molecule system to illustrate our results. In particular, with this method, we compute the curvature for Hannay's angle analytically, and compare it to the Berry curvature obtained with the second-quantized model of the same system. An excellent agreement is found, indicating the validity of our method.展开更多
The octupole deformations and other ground state properties of even-even Rn, Th and U isotopes are investigated systematically within the framework of the reflection asymmetric relativistic mean field (RAS-RMF) mode...The octupole deformations and other ground state properties of even-even Rn, Th and U isotopes are investigated systematically within the framework of the reflection asymmetric relativistic mean field (RAS-RMF) model. The calculation results reproduce the binding energies and the quadrupole deformations well. The calculation results indicate these nuclei at ground states evolve from neaxly-spherical (N = 130) shape to quadrupole deformation shape with the increase of the neutron number. It is also found that among the Rn isotopes, only^222,224 Rn axe oetupole deformed and the octupole deformations for them are small. However, more nuclei (N ≌ 134 148) in Th and U isotopes are octupole deformed and the octupole deformations for some of them are significant (|β3|- 0.1 or even larger).展开更多
The influences of hyperon-hyperon interaction on the overall properties of hadronic star are investigated in the framework of relativistic mean field (RMF) theory. For certain hyperon coupling, the weaker hyperon-hy...The influences of hyperon-hyperon interaction on the overall properties of hadronic star are investigated in the framework of relativistic mean field (RMF) theory. For certain hyperon coupling, the weaker hyperon-hyperon interaction can lead to the heavier hadronic star, which accords with the observation of heavy neutron star in X-ray binaries. We find that the threshold densities of the hyperons with larger masses are brought to a lower values with the increase of the hyperon-hyperon interaction. The possibility of the existence of hyperon star is checked with the consideration of hyperon-hyperon interaction.展开更多
The effects of σ^* and Ф mesons on the surface redshift of a neutron star have been investigated within the framework of relativistic mean field theory for the baryon octet {n, p, ∧, ∑-,∑0, ∑+, -, 0} syste...The effects of σ^* and Ф mesons on the surface redshift of a neutron star have been investigated within the framework of relativistic mean field theory for the baryon octet {n, p, ∧, ∑-,∑0, ∑+, -, 0} system. It is found that compared with those without considering the contributions of σ^* and Ф mesons, the surface redshift decreases and that corresponding to the maximum value of the mass also decreases from 0.2540 to 0.2236, about by 12%. Meanwhile, it is also found that including σ^* and Ф mesons, the M/R and that corresponding to the maximum mass decrease.展开更多
Modern computer simulations of biological systems often involve an explicit treatment of the complex interactions among a large number of molecules. While it is straightforward to compute the short-ranged Van der Waal...Modern computer simulations of biological systems often involve an explicit treatment of the complex interactions among a large number of molecules. While it is straightforward to compute the short-ranged Van der Waals interaction in classical molecular dynamics simulations, it has been a long-lasting issue to develop accurate methods for the longranged Coulomb interaction. In this short review, we discuss three types of methodologies for the accurate treatment of electrostatics in simulations of explicit molecules: truncation-type methods, Ewald-type methods, and mean-field-type methods. Throughout the discussion, we brief the formulations and developments of these methods, emphasize the intrinsic connections among the three types of methods, and focus on the existing problems which are often associated with the boundary conditions of electrostatics. This brief survey is summarized with a short perspective on future trends along the method developments and applications in the field of biological simulations.展开更多
The Poisson–Boltzmann(PB)theory is one of the most important theoretical models describing charged systems continuously.However,it suffers from neglecting ion correlations,which hinders its applicability to more gene...The Poisson–Boltzmann(PB)theory is one of the most important theoretical models describing charged systems continuously.However,it suffers from neglecting ion correlations,which hinders its applicability to more general charged systems other than extremely dilute ones.Therefore,some modified versions of the PB theory are developed to effectively include ion correlations.Focused on their applications to ionic solutions,the original PB theory and its variances,including the field-theoretic approach,the correlation-enhanced PB model,the Outhwaite–Bhuiyan modified PB theory and the mean field theories,are briefly reviewed in this paper with the diagnosis of their advantages and limitations.展开更多
The in-medium feature of nuclear force, which includes both nucleon-nucleon( NN) and hyperon-nucleon( ΛN) interactions, impacts the description of single-Λ hypernuclei. With the alternated mass number or isospin of ...The in-medium feature of nuclear force, which includes both nucleon-nucleon( NN) and hyperon-nucleon( ΛN) interactions, impacts the description of single-Λ hypernuclei. With the alternated mass number or isospin of hypernuclei, such effects may be unveiled by analyzing the systematic evolution of the bulk and single-particle properties. From a density-dependent meson-nucleon/hyperon coupling perspective, a new ΛN effective interaction in the covariant density functional(CDF) theory, namely, DD-LZ1-Λ1, is obtained by fitting the experimental data ofΛ separation energies for several single-Λ hypernuclei. It is then used to study the structure and transition properties of single-Λ hypernuclei in oxygen hyperisotopes, in comparison with those determined using several selected CDF Lagrangians. A discrepancy is explicitly observed in the isospin evolution of Λ1p spin-orbit splitting with various effective interactions, which is attributed to the divergence of the meson-hyperon coupling strengths with increasing density. In particular, the density-dependent CDFs introduce an extra contribution to reduce the value but enhance the isospin dependence of the splitting, which originates from the rearrangement terms of Λ self-energies. In addition, the characteristics of hypernuclear radii are studied along the isotopic chain. Owing to the impurity effect of theΛ hyperon, a size shrinkage is observed in the matter radii of hypernuclei compared with the cores of normal nuclei,and its magnitude is further elucidated to correlate with the incompressibility of nuclear matter. Moreover, there is a sizable model-dependent trend in which the Λ hyperon radii evolve with neutron number, which is decided partly by the in-medium NN interactions and core polarization effects.展开更多
Deformation constrained relativistic mean-field (RMF) approach with fixed configuration and timeodd component has been developed and applied to investigate magnetic moments of light nuclei near doublyclosed shells. Ta...Deformation constrained relativistic mean-field (RMF) approach with fixed configuration and timeodd component has been developed and applied to investigate magnetic moments of light nuclei near doublyclosed shells. Taking 17O as an example, the results and discussion are given in detail.展开更多
文摘We present a formalism of charge self-consistent dynamical mean field theory(DMFT)in combination with densityfunctional theory(DFT)within the linear combination of numerical atomic orbitals(LCNAO)framework.We implementedthe charge self-consistent DFT+DMFT formalism by interfacing a full-potential all-electron DFT code with threehybridization expansion-based continuous-time quantum Monte Carlo impurity solvers.The benchmarks on several 3d,4fand 5f strongly correlated electron systems validated our formalism and implementation.Furthermore,within the LCANOframework,our formalism is general and the code architecture is extensible,so it can work as a bridge merging differentLCNAO DFT packages and impurity solvers to do charge self-consistent DFT+DMFT calculations.
文摘Established on the framework of Frege's philosophy of language, with the help of Tarlski in the development on the innovation oftheory of truth (including methodology level), Davidson explained the concept of meaning in the process of language Ibrmation with the interpretation and characterization of"the formalization of axis" which was Developing from "t refers to x" to "s means m ", then to" s means that p", then to " (T) s is T if and only ifp". After a series of ideas conversion on the restructuring and improvement, Davidson finally created an innovative view of meaning on the holistic level. In order to realize the meaning of language itself as the axis, with Tarski's theory of truth as the transmission fulcrum, with natural language translation and interpretation as the actual operation range, he has run the theory of meaning as the understanding, interpretation and action picture of people dealing with events arranged in a crisscross pattern world.
基金Project supported by the National Natural Science Foundation of China (Grant No 60476047)the Natural Science Foundation of Henan Province, China (Grant No 0411011700)
文摘A combination of the iterative perturbation theory (ITP) of the dynamical mean field theory (DMFT) and coherentpotential approximation (CPA) is generalized to the double exchange model with orbital degeneracy. The Hubbard interaction and the off-diagonal components for the hopping matrix tij^mn(m ≠ n) are considered in our calculation of spectrum and optical conductivity. The numerical results show that the effects of the non-diagonal hopping matrix elements are important.
基金supported by the National Natural Science Foundation of China(Grant Nos.21421001,21373118,and 21203100)the Natural Science Foundation of Tianjin,China(Grant No.13JCQNJC06700)+1 种基金the MOE Innovation Team of China(Grant No.IRT13022)NFFTBS(Grant No.J1103306)
文摘In order to understand the electric interfacial behavior, mean field based electric double layer (EDL) theory has been continuously developed over the past 150 years. In this article, we briefly review the development of the EDL model, from the dimensionless Gouy-Chapman model to the symmetric Bikerman-Freise model, and finally toward size-asymmetric mean field theory models. We provide the general derivations within the framework of Helmholtz free energy of the lattice- gas model, and it can be seen that the above-mentioned models are consistent in the sense that the interconversi0n among them can be achieved by reducing the basic assumptions.
基金supported by the National Natural Science Foundation of China(Grant Nos.11174169,11234007,and 51471093)
文摘We investigate the effect of interaction, temperature, and anisotropic parameter on the quantum phase transitions in an anisotropic square-octagon lattice with fermions under the framework of the single band Hubbard model through using the combination of cellular dynamical mean field theory and a continuous time Monte Carlo algorithm. The competition between interaction and temperature shows that with the increase of the anisotropic parameter, the critical on-site repulsive interaction for the metal-insulator transition increases for fixed temperature. The interaction-anisotropic parameter phase diagram reveals that with the decrease of temperature, the critical anisotropic parameter for the Mott transition will increase for fixed interaction cases.
基金Supported by the Nature Science Foundation of China under Grant Nos.10875003 and 10811240152the calculations are supported by CERNET High Performance Computing Center in China
文摘We propose a quantization procedure for the nucleon-scMar meson system, in which an arbitrary mean scalar meson field Ф is introduced. The equivalence of this procedure with the usual one is proven for any given value of qS. By use of this procedure, the scalar meson field in the Walecka's MFA and in Chin's RHA are quantized around the mean field, Its corrections on these theories are considered by perturbation up to the second order. The arbitrariness of Ф makes us free to fix it at any stage in the calculation. When we fix it in the way of Walecka's MFA, the quantum corrections are big, and the result does not converge. When we fix it in the way of Chin's RHA, the quantum correction is negligibly small, and the convergence is excellent. It shows that RHA covers the leading part of quantum field theory for nuclear systems and is an excellent zeroth order approximation for further quantum corrections, while the Walecka's MFA does not. We suggest to fix the parameter Ф at the end of the whole calculation by minimizing the total energy per-nucleon for the nuclear matter or the total energy for the finite nucleus, to make the quantized relativistic mean field theory (QRMFT) a variational method.
基金Supported by National Natural Science Foundation of China under Grant Nos. 10735010, 10975072, and 11035001, by 973 National Major State Basic Research and Development of China under Grant No. 2007CB815004 and 2010CB327803, CAS Knowledge Innovation Project under Grant No. KJCX2-SW-N02, and by Research Fund of Doctoral Point under Grant No. 20100091110028
文摘The newly synthesized element 117 and its alpha-decay chains are systematically investigated in the framework of the relativistic mean field theory with parameter sets NL-Z2 and TMA. The ground-state properties of the superheavy nuclei on the alpha-decay chains of 294 117 and 293 117 are calculated. The experimental alpha-decay energies and ha Jr-lives of the two alpha-decay chains are reasonably reproduced by the model The detailed discussions on the binding energies, alpha-decay energies, half-lives, quadrupole deformations, potential energy curves, and single particle levels of the two alpha-decay chains are made.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.10334090,10425418,60576058)the National Basic Research Program of China(Grant No.2007CB925000)
文摘This paper proposes an impurity solver for the dynamical mean field theory (DMFT) study of the Mott insulators, which is based on the second order perturbation of the hybridization function. After careful benchmarking with quantum Monte Carlo results on the anti-ferromagnetic phase of the Hubbard model, it concludes that this impurity solver can capture the main physical features in the strong coupling regime and can be a very useful tool for the LDA (local density approximation) + DMFT studies of the Mort insulators with long range order.
基金Supported by National Natural Science Foundation of China under Grant Nos.10535010 and 10775068973 National Major State Basic Research and Development of China (2007CB815004)+2 种基金CAS Knowledge Innovation Project (KJCX2-SW-N02)Research Fund of Education Ministry under contract RFDP (20070284016)Green-blue Project of Jiangsu Province
文摘The nuclei around magic number N=126 are investigated in the deformed relativistic mean field (RMF)model with effective interactions TMA.We focus investigations on the N=126 isotonic chain.The N=126 shellevolution is studied by analyzing the variations of two-neutron (proton) separation energies,quadruple deformations,single particle levels etc.The good agreement of two-neutron separation energies between experimental data and calculatedvalues is reached.The RMF theory predicts that the sizes of N=126 shell become smaller and smaller withthe increasing of proton number Z.However,the N=126 shell exists in our calculated region all along.According tothe calculated two-proton separation energies,the RMF theory suggests ^(220)Pu is a two-proton drip-line nucleus in theN=126 isotonic chain.
文摘Phase diagram and thermodynamic parameters of the random field Ising model (RFIM) on spherical lattice are studied by using mean field theory. This lattice is placed in an external magnetic field (B). The random field (hi) is assumed to be Gaussian distributed with zero mean and a variance (hi2) = HRF2. The free energy (F), the magnetization (M) and the order parameter (q) are calculated. The ferromagnetic (FM) spin-glass (SG) phase transition is clearly observed. The critical temperature (Tc) is computed under a critical intensity of random field HRF = V/2/πJ. The phase transition from FM to paramagnetic (PM) occurs at TC = J/k in the absence of magnetic field. The critical temperature decreases as HRF increases in the phase boundary of FM-to-SG. The magnetic susceptibility (X) shows a sharp cusp at TC and the specific heat (C) has a singularity in small random field. The internal energy (U) has a similar behaviour to that obtained from the Monte Carlo simulation.
基金Supported by the National Natural Science Foundation of China under Grant Nos.10535010,10675090,10775068,and 10975072the 973 National Major State Basic Research and Development of China under Grant No.2007CB815004+1 种基金CAS Knowledge Innovation Project KJCX2-SW-N02the Research Fund of Doctoral Point (RFDP) under Grant No.20070284016
文摘Relativistic mean-field theory and phase-shift analysis are combined together to investigate the elasticCoulomb scattering between electrons and unstable nuclei.Electron scattering at several different energies is studiedand compared,in order to see the energy dependence of electron-nucleus scattering.It is shown that electron scattering at200 MeV or 300 MeV can be used to reveal electron-nucleus scattering information around the first diffraction minimum-Shiftsin opposite directions are obtained for the first diffraction minima of the electron scattering off the ground andfirst excited states of ^(17)F with ^(16)O as reference,and similar effects are obtained for ^(18)Ne.Besides,some neutron-richN = 8 isotones are also studied.Results show that electron scattering will be very useful and important in studyingboth proton- and neutron-rich nuclei in the future.
基金supported by National Natural Science Foundation of China (Nos. 10535010, 10675090, 10775068, 10735010, 10975072, 11035001)973 National Major State Basic Research and Development of China (Nos. 2007CB815004, 2010CB327803)+2 种基金CAS Knowledge Innovation Project (No. KJCX2-SW-N02)Research Fund of Doctoral Point (RFDP) (No. 20070284016)Science Foundation of Educational Committee of Anhui Province(No. KJ2012A083)
文摘In this work, the ground-state properties of Pt, Hg, Pb, and Po isotopes have been systematically investigated in the deformed relativistic mean field (RMF) theory with the new parameter set FSUGold. The calculated results show that FSUGold is as successful as NL3 in reproducing the ground-state binding energies of the nuclei in this region. The calculated two- neutron separation energies, quadrupole deformations, and root-mean-square charge radii are in agreement with the experimental data. The parameter set FSUGold can successfully describe the shell effect of the neutron magic number N = 126 and give smaller neutron skin thicknesses than NL3 for all the nuclei considered.
基金Project supported by the National Natural Science Foundation of China (Grant No. 10825417)
文摘In the mean-field theory of atom-molecule systems, where the bosonic atoms combine to form molecules, there is no usual U(1) symmetry, which presents an apparent hurdle for calculating the Berry connection in these systems. We develop a perturbation expansion method of Hannay's angle suitable for calculating the Berry curvature in the atom- molecule systems. With this Berry curvature, the Berry connection can be computed naturally. We use a three-level atom-molecule system to illustrate our results. In particular, with this method, we compute the curvature for Hannay's angle analytically, and compare it to the Berry curvature obtained with the second-quantized model of the same system. An excellent agreement is found, indicating the validity of our method.
基金Supported by National Natural Science Foundation of China under Grant Nos.10975100, 10979024, 10705014, and 10811130562The Knowledge Innovation Project of the Chinese Academy of Sciences under Grant No.KJCX3-SYW-No2Major State Basic Research Development Program under Grant No.2007CB815000
文摘The octupole deformations and other ground state properties of even-even Rn, Th and U isotopes are investigated systematically within the framework of the reflection asymmetric relativistic mean field (RAS-RMF) model. The calculation results reproduce the binding energies and the quadrupole deformations well. The calculation results indicate these nuclei at ground states evolve from neaxly-spherical (N = 130) shape to quadrupole deformation shape with the increase of the neutron number. It is also found that among the Rn isotopes, only^222,224 Rn axe oetupole deformed and the octupole deformations for them are small. However, more nuclei (N ≌ 134 148) in Th and U isotopes are octupole deformed and the octupole deformations for some of them are significant (|β3|- 0.1 or even larger).
文摘The influences of hyperon-hyperon interaction on the overall properties of hadronic star are investigated in the framework of relativistic mean field (RMF) theory. For certain hyperon coupling, the weaker hyperon-hyperon interaction can lead to the heavier hadronic star, which accords with the observation of heavy neutron star in X-ray binaries. We find that the threshold densities of the hyperons with larger masses are brought to a lower values with the increase of the hyperon-hyperon interaction. The possibility of the existence of hyperon star is checked with the consideration of hyperon-hyperon interaction.
基金supported by the Science Research Program of Institutions of Higher Education of Anhui Province,China (Grant No. KJ2009B106)the Science Research Program of Chuzhou University,China (Grant No. 2008kj019B)the Scientific Research Starting Foundation for Doctoral Scientists of Chuzhou University,China
文摘The effects of σ^* and Ф mesons on the surface redshift of a neutron star have been investigated within the framework of relativistic mean field theory for the baryon octet {n, p, ∧, ∑-,∑0, ∑+, -, 0} system. It is found that compared with those without considering the contributions of σ^* and Ф mesons, the surface redshift decreases and that corresponding to the maximum value of the mass also decreases from 0.2540 to 0.2236, about by 12%. Meanwhile, it is also found that including σ^* and Ф mesons, the M/R and that corresponding to the maximum mass decrease.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.91127015 and 21522304)the Open Project from the State Key Laboratory of Theoretical Physicsthe Innovation Project from the State Key Laboratory of Supramolecular Structure and Materials
文摘Modern computer simulations of biological systems often involve an explicit treatment of the complex interactions among a large number of molecules. While it is straightforward to compute the short-ranged Van der Waals interaction in classical molecular dynamics simulations, it has been a long-lasting issue to develop accurate methods for the longranged Coulomb interaction. In this short review, we discuss three types of methodologies for the accurate treatment of electrostatics in simulations of explicit molecules: truncation-type methods, Ewald-type methods, and mean-field-type methods. Throughout the discussion, we brief the formulations and developments of these methods, emphasize the intrinsic connections among the three types of methods, and focus on the existing problems which are often associated with the boundary conditions of electrostatics. This brief survey is summarized with a short perspective on future trends along the method developments and applications in the field of biological simulations.
基金supported by the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDA17010504)the National Natural Science Foundation of China(Nos.11774357 and 11947302)the CAS Biophysics Interdisciplinary Innovation Team Project(No.2060299)。
文摘The Poisson–Boltzmann(PB)theory is one of the most important theoretical models describing charged systems continuously.However,it suffers from neglecting ion correlations,which hinders its applicability to more general charged systems other than extremely dilute ones.Therefore,some modified versions of the PB theory are developed to effectively include ion correlations.Focused on their applications to ionic solutions,the original PB theory and its variances,including the field-theoretic approach,the correlation-enhanced PB model,the Outhwaite–Bhuiyan modified PB theory and the mean field theories,are briefly reviewed in this paper with the diagnosis of their advantages and limitations.
基金the Fundamental Research Funds for the Central Universities,Lanzhou University(lzujbky-2022-sp02,lzujbky-2023-stlt01)the National Natural Science Foundation of China(11875152,12275111)the Strategic Priority Research Program of Chinese Academy of Sciences(XDB34000000)。
文摘The in-medium feature of nuclear force, which includes both nucleon-nucleon( NN) and hyperon-nucleon( ΛN) interactions, impacts the description of single-Λ hypernuclei. With the alternated mass number or isospin of hypernuclei, such effects may be unveiled by analyzing the systematic evolution of the bulk and single-particle properties. From a density-dependent meson-nucleon/hyperon coupling perspective, a new ΛN effective interaction in the covariant density functional(CDF) theory, namely, DD-LZ1-Λ1, is obtained by fitting the experimental data ofΛ separation energies for several single-Λ hypernuclei. It is then used to study the structure and transition properties of single-Λ hypernuclei in oxygen hyperisotopes, in comparison with those determined using several selected CDF Lagrangians. A discrepancy is explicitly observed in the isospin evolution of Λ1p spin-orbit splitting with various effective interactions, which is attributed to the divergence of the meson-hyperon coupling strengths with increasing density. In particular, the density-dependent CDFs introduce an extra contribution to reduce the value but enhance the isospin dependence of the splitting, which originates from the rearrangement terms of Λ self-energies. In addition, the characteristics of hypernuclear radii are studied along the isotopic chain. Owing to the impurity effect of theΛ hyperon, a size shrinkage is observed in the matter radii of hypernuclei compared with the cores of normal nuclei,and its magnitude is further elucidated to correlate with the incompressibility of nuclear matter. Moreover, there is a sizable model-dependent trend in which the Λ hyperon radii evolve with neutron number, which is decided partly by the in-medium NN interactions and core polarization effects.
基金Supported by National Natural Science Foundation of China (10505002, 10435010, 10605001, 10221003)Postdoctoral Science Foundation of China (20060390371)
文摘Deformation constrained relativistic mean-field (RMF) approach with fixed configuration and timeodd component has been developed and applied to investigate magnetic moments of light nuclei near doublyclosed shells. Taking 17O as an example, the results and discussion are given in detail.