2018年8月20日
Strang splitting in combination with rank-$1$ and rank-$r$ lattices for the time-dependent Schrödinger equation
SIAM Journal on Scientific Computing. 41.6 (2019), B1254-B1283
- 記述言語
- 掲載種別
- 研究論文(学術雑誌)
- DOI
- 10.1137/18m1207879
We approximate the solution for the time dependent Schrödinger equation (TDSE) in two steps. We first use a pseudo-spectral collocation method that uses samples of functions on rank-1 or rank-r lattice points with unitary Fourier transforms. We then get a system of ordinary differential equations in time, which we solve approximately by stepping in time using the Strang splitting method. We prove that the numerical scheme proposed converges quadratically with respect to the time step size, given that the potential is in a Korobov space with the smoothness parameter greater than $9/2$. Particularly, we prove that the required degree of smoothness is independent of the dimension of the problem. We demonstrate our new method by comparing with results using sparse grids from [12 ] , with several numerical examples showing large advantage for our new method and pushing the examples to higher dimensionality. The proposed method has two distinctive features from a numerical perspective: (i) numerical results show the error c onvergence of time discretization is consistent even for higher-dimensional problems; (ii) by using the rank-$1$ lattice points, the solution can be efficiently computed (and further time stepped) using only $1$-dimensional Fast Fourier Transforms.
- ID情報
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- DOI : 10.1137/18m1207879
- ORCIDのPut Code : 84034287
- arXiv ID : arXiv:1808.06357