In this study, the rapidity distribution, collective flows, and nuclear stopping power in ^(197)Au+^(197)Au collisions at intermediate energies were investigated using the ultrarelativistic quantum molecular dynamics(...In this study, the rapidity distribution, collective flows, and nuclear stopping power in ^(197)Au+^(197)Au collisions at intermediate energies were investigated using the ultrarelativistic quantum molecular dynamics(UrQMD) model with GEMINI++ code. The UrQMD model was adopted to simulate the dynamic evolution of heavy-ion collisions, whereas the GEMINI++ code was used to simulate the decay of primary fragments produced by UrQMD. The calculated results were compared with the INDRA and FOPI experimental data. It was found that the rapidity distribution, collective flows, and nuclear stopping power were affected to a certain extent by the decay of primary fragments, especially at lower beam energies. Furthermore, the experimental data of the collective flows and nuclear stopping power at the investigated beam energies were better reproduced when the sequential decay effect was included.展开更多
Spin-wave excitation plays important roles in the investigation of the magnetic phases. In this paper, we study the spin-wave excitation spectra of two-component Bose gases with spin-orbit coupling in a deep square op...Spin-wave excitation plays important roles in the investigation of the magnetic phases. In this paper, we study the spin-wave excitation spectra of two-component Bose gases with spin-orbit coupling in a deep square optical lattice using the spin-wave theory. We find that, while the excitation spectrum of the vortex crystal phase is gapless with a linear dispersion in the vicinity of the minimum point, the spectra of the commensurate spiral spin phase and the skyrmion crystal phase are gapped. Significantly, the spin fluctuations strongly destabilize the classical ground state of the skyrmion phase with the appearance of an imaginary part in the eigenfrequencies of spin excitations. Such features of the spin excitation spectra provide further insights into the exotic spin phases.展开更多
We use the iterative unitary matrix multiplication method to calculate the long-time behaviour of the resonant quantum kicked rotator with a large denominator. The delocalization time is an exponential function of the...We use the iterative unitary matrix multiplication method to calculate the long-time behaviour of the resonant quantum kicked rotator with a large denominator. The delocalization time is an exponential function of the denominator. The wave function delocalizes through degenerate states. We also construct a nonresonant quantum kicked rotator with delocalization.展开更多
Time evolution of ionospheric D-region plasmas including the perturbations of electrons and charged aerosol particles is investigated under the conditions of polar mesosphere summer echoes (PMSE). It is shown that t...Time evolution of ionospheric D-region plasmas including the perturbations of electrons and charged aerosol particles is investigated under the conditions of polar mesosphere summer echoes (PMSE). It is shown that the time scale of decay of the electron density is in the order of an hour under typical PMSE conditions, in the majority of cases, the electron density is anticorrelated to the ion density, except that the radius of aerosol particles is greater than 50 nm. Also, the evolutions under varied parameters, such as the amplitude and width of perturbation, the aerosol particle radius, and the altitude of the PMSE occurrence are investigated. The obtained results are useful for interpreting the experimental observations.展开更多
The multiplicity difference correlators between two well-separated bins are studied in second-order quark-gluon plasma(QGP)phase transition within the Ginzburg-Landau model.For the case with very low mean multipliciti...The multiplicity difference correlators between two well-separated bins are studied in second-order quark-gluon plasma(QGP)phase transition within the Ginzburg-Landau model.For the case with very low mean multiplicities,an exponentγis found,which has very weak dependence on the parameters of the model and can be used as a signal for the formation of QGP in ultra-relativistic heavy-ion collisions.展开更多
The interlayer hybridization(IH)of van der Waals(vdW)materials is thought to be mostly associated with the unignorable interlayer overlaps of wavefunctions(t)in real space.Here,we develop a more fundamental understand...The interlayer hybridization(IH)of van der Waals(vdW)materials is thought to be mostly associated with the unignorable interlayer overlaps of wavefunctions(t)in real space.Here,we develop a more fundamental understanding of IH by introducing a new physical quantity,the IH admixture ratioα.Consequently,an exotic strategy of IH engineering in energy space can be proposed,i.e.,instead of changing t as commonly used,αcan be effectively tuned in energy space by changing the on-site energy difference(2Δ)between neighboring-layer states.In practice,this is feasible via reshaping the electrostatic potential of the surface by deposing a dipolar overlayer,e.g.,crystalline ice.Our first-principles calculations unveil that IH engineering via adjusting 2Δcan greatly tune interlayer optical transitions in transition-metal dichalcogenide bilayers,switch different types of Dirac surface states in Bi_(2)Se_(3)thin films,and control magnetic phase transition of charge density waves in 1H/1T-TaS_(2)bilayers,opening new opportunities to govern the fundamental optoelectronic,topological,and magnetic properties of vdW systems beyond the traditional interlayer distance or twisting engineering.展开更多
基金partly supported by the National Natural Science Foundation of China (Nos. U2032145 and 11875125)the National Key Research and Development Program of China (No. 2020YFE0202002)。
文摘In this study, the rapidity distribution, collective flows, and nuclear stopping power in ^(197)Au+^(197)Au collisions at intermediate energies were investigated using the ultrarelativistic quantum molecular dynamics(UrQMD) model with GEMINI++ code. The UrQMD model was adopted to simulate the dynamic evolution of heavy-ion collisions, whereas the GEMINI++ code was used to simulate the decay of primary fragments produced by UrQMD. The calculated results were compared with the INDRA and FOPI experimental data. It was found that the rapidity distribution, collective flows, and nuclear stopping power were affected to a certain extent by the decay of primary fragments, especially at lower beam energies. Furthermore, the experimental data of the collective flows and nuclear stopping power at the investigated beam energies were better reproduced when the sequential decay effect was included.
基金supported by the National Natural Science Foundation of China(Grant Nos.11347197,11404225,and 11474205)
文摘Spin-wave excitation plays important roles in the investigation of the magnetic phases. In this paper, we study the spin-wave excitation spectra of two-component Bose gases with spin-orbit coupling in a deep square optical lattice using the spin-wave theory. We find that, while the excitation spectrum of the vortex crystal phase is gapless with a linear dispersion in the vicinity of the minimum point, the spectra of the commensurate spiral spin phase and the skyrmion crystal phase are gapped. Significantly, the spin fluctuations strongly destabilize the classical ground state of the skyrmion phase with the appearance of an imaginary part in the eigenfrequencies of spin excitations. Such features of the spin excitation spectra provide further insights into the exotic spin phases.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10674125 and 10475070, and the National Basic Research Programme of China under Grant No 2007CB925200.
文摘We use the iterative unitary matrix multiplication method to calculate the long-time behaviour of the resonant quantum kicked rotator with a large denominator. The delocalization time is an exponential function of the denominator. The wave function delocalizes through degenerate states. We also construct a nonresonant quantum kicked rotator with delocalization.
基金supported by National Natural Science Foundation of China (Nos. 40831062, 10775134)partially supported by CAS Knowledge Innovation Program (No. kjcx2-yw-n28)National Basic Research Program of China (Nos. 2008CB717800, 2009GB105001)
文摘Time evolution of ionospheric D-region plasmas including the perturbations of electrons and charged aerosol particles is investigated under the conditions of polar mesosphere summer echoes (PMSE). It is shown that the time scale of decay of the electron density is in the order of an hour under typical PMSE conditions, in the majority of cases, the electron density is anticorrelated to the ion density, except that the radius of aerosol particles is greater than 50 nm. Also, the evolutions under varied parameters, such as the amplitude and width of perturbation, the aerosol particle radius, and the altitude of the PMSE occurrence are investigated. The obtained results are useful for interpreting the experimental observations.
基金Supported in part by the National Natural Science Foundation of China under Grant No.19875019the Natural Science Foundation of Hubei Province,and the Die Deutsche Forschungsgemeinschaft in Germany.
文摘The multiplicity difference correlators between two well-separated bins are studied in second-order quark-gluon plasma(QGP)phase transition within the Ginzburg-Landau model.For the case with very low mean multiplicities,an exponentγis found,which has very weak dependence on the parameters of the model and can be used as a signal for the formation of QGP in ultra-relativistic heavy-ion collisions.
基金supported by the National Key R&D Program of China(Grant No.2022YFA1504000)the National Natural Science Foundation of China(Grant Nos.12088101,U2230402)+1 种基金the Tianjin Natural Science Foundation(Grant No.20JCZDJC00750)the Deutsche Forschungsgemeinschaft(DFG)(Grant No.EXC 2077)。
文摘The interlayer hybridization(IH)of van der Waals(vdW)materials is thought to be mostly associated with the unignorable interlayer overlaps of wavefunctions(t)in real space.Here,we develop a more fundamental understanding of IH by introducing a new physical quantity,the IH admixture ratioα.Consequently,an exotic strategy of IH engineering in energy space can be proposed,i.e.,instead of changing t as commonly used,αcan be effectively tuned in energy space by changing the on-site energy difference(2Δ)between neighboring-layer states.In practice,this is feasible via reshaping the electrostatic potential of the surface by deposing a dipolar overlayer,e.g.,crystalline ice.Our first-principles calculations unveil that IH engineering via adjusting 2Δcan greatly tune interlayer optical transitions in transition-metal dichalcogenide bilayers,switch different types of Dirac surface states in Bi_(2)Se_(3)thin films,and control magnetic phase transition of charge density waves in 1H/1T-TaS_(2)bilayers,opening new opportunities to govern the fundamental optoelectronic,topological,and magnetic properties of vdW systems beyond the traditional interlayer distance or twisting engineering.