A space-time Trefftz discontinuous Galerkin method for the Schr\"odinger equation with piecewise-constant potential is proposed and analyzed. Following the spirit of Trefftz methods, trial and test spaces are spanned by non-polynomial complex wave functions that satisfy the Schro\"odinger equation locally on each element of the space-time mesh. This allows for a significant reduction in the number of degrees of freedom in comparison with full polynomial spaces. We prove well-posedness and stability of the method, and, for the one- and two- dimensional cases, optimal, high-order, h-convergence error estimates in a skeleton norm. Some numerical experiments validate the theoretical results presented.
翻译:根据Trefftz方法的精神,试验和试验空间由非球状复合波的函数跨越,这些函数在时空网格的每个元素上都能满足Schro\'doginger等式的局部等式。这样可以大大降低与整个多元空间相比的自由度。我们证明,这种方法具有很好的储存性和稳定性,对于一维和二维案例,在骨骼规范中,对一维和二维案例,最佳的、高度的、h-convergle错误估计是最佳的。一些数字实验证实了所提出的理论结果。