模拟Bose-Fermi混合气体在绝对零度温度下动力学的一种时间分裂有限差分法
A Splitting Finite Difference Method for Simulating the Dynamics of Mixture of Bose-Fermi Gas at Zero Temperature
摘要: 在耦合Gross-Pitaevskii方程组数值解的基础上,我们探讨在绝对零度下Bose-Fermi混合物的动力学规律。为了计算简便,我们首先把最初的耦合Gross-Pitaevskii方程组转化为无量纲形式方程组,然后把无量纲三维形式方程组简化成二维形式再进一步简化为一维形式,并证明了与耦合Gross-Pitaevskii方程组相关的守恒律——模量守恒以及能量守恒。其次,为了探讨Bose-Fermi混合物的动力学规律,我们提出了一种高效的数值方法——时间分裂差分法来求解耦合Gross-Pitaevskii方程组。并证明了该数值方法具有无条件稳定性以及保持耦合Gross-Pitaevskii方程组守恒律等优点。最后利用该方法来数值模拟Bose-Fermi混合物的动力学规律。
Abstract: In this paper, based on the numerical solutions of coupled Gross-Pitaevskii equations, we investigate the dynamics of Bose-Fermi mixtures at zero temperature. Firstly, to simplify the numerical computation, we reformulate the equations into three-dimensional dimensionless ones, which are also further reduced to two-dimensional ones and one-dimensional ones. Secondly, to compute the numerical solutions, we present a high-efficiency method for the equations, the time-splitting difference method. We have proved that the method is unconditionally stable and keeps well the related conservation laws. Lastly we apply the method into studying the dynamics of Bose-Fermi mixtures.
文章引用:张志红, 高文, 王伟民. 模拟Bose-Fermi混合气体在绝对零度温度下动力学的一种时间分裂有限差分法[J]. 应用数学进展, 2018, 7(4): 401-412. https://doi.org/10.12677/AAM.2018.74050

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