Wavepacket dynamics on arbitrary Lagrangian–Eulerian grids: Application to an Eckart barrier
Wavepacket dynamics on arbitrary Lagrangian–Eulerian grids: Application to an Eckart barrier
复制标题
任意拉格朗日-欧拉网格上的波包动力学：在埃卡特势垒中的应用
DOI：
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发表时间：
2003
期刊：
影响因子：
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通讯作者：
R. Wyatt
中科院分区：
文献类型：
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作者：
K. Hughes;R. Wyatt
描述了一种自适应网格方法，用于计算研究来自排斥性Eckart势垒的波包散射。网格在任意拉格朗日-欧拉（ALE）框架内运动，运动方程采用薛定谔方程和流体动力学方程的运动路径变换的混合形式。边界网格点遵循拉格朗日轨迹，而内部网格点遵循非拉格朗日路径。对于流体动力学方程，内部网格点在拉格朗日边界之间的间隔是相等的。对于薛定谔方程的运动路径变换，内部网格分布是由等分布原理决定的，通过网格平滑技术，这些网格点沿着一个连续适应的路径来反映波包的动态。移动网格技术具有鲁棒性，可以在波包传播时间超过5ps的情况下，使用少量网格点进行精确计算。
An adaptive grid approach to a computational study of the scattering of a wavepacket from a repulsive Eckart barrier is described. The grids move in an arbitrary Lagrangian–Eulerian (ALE) framework and a hybrid of the moving path transform of the Schrodinger equation and the hydrodynamic equations are used for the equations of motion. Boundary grid points follow Lagrangian trajectories and interior grid points follow non-Lagrangian paths. For the hydrodynamic equations the interior grid points are equally spaced between the evolving Lagrangian boundaries. For the moving path transform of the Schrodinger equation interior grid distribution is determined by the principle of equidistribution, and by using a grid smoothing technique these grid points trace a path that continuously adapts to reflect the dynamics of the wavepacket. The moving grid technique is robust and allows accurate computations to be obtained with a small number of grid points for wavepacket propagation times exceeding 5 ps.