A nonlinear Schrodinger equation in one-dimensional bead chain is first obtained and an envelope solitary wave of the system is verified numerically in this system. The reflection and the transmission of an incident envelope solitary wave due to impurities has also been investigated. It is found that the magnitudes of both the reflection and the transmission not only depend on the characters of impurity materials, the wave number, the incident wave amplitude, but also on the impurity number. This can be used to detect the character and the number of the impurity materials in the bead chain by measuring the reflection and the transmission of an incident pulse.
We investigate the tunneling dynamics of the Fermi gases in an optical lattice in the Bose--Einstein condensation （BEC） regime. The three critical scattering lengths and the system energies are found in different cases of Josephson oscillation （JO）, oscillating-phase-type self-trapping （OPTST）, running-phase-type self-trapping （RPTST）, and self-trapping （ST）. It is found that the s-wave scattering lengths have a crucial role on the tunneling dynamics. By adjusting the scattering length in the adiabatic condition, the transition probability changes with the adiabatic periodicity and a rectangular periodic pattern emerges. The periodicity of the rectangular wave depends on the system parameters such as the periodicity of the adjustable parameter, the s-wave scattering length.
基于单质全局物态方程模型QEOS(Quotidian equation of state),通过求解平均原子模型的混合物Thomas-Fermi方程以及将混合元素平均为单一虚拟元素的方法得到了混合物状态方程。对铅铋混合物LBE的物态方程做了初步研究,计算了LBE在给定温度与密度下的压强、电离度等,并分析了电离平衡和不同温度、密度下电子及离子对总压强的贡献。
