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arXiv · 2607.04835

Arbitrary high order splitting methods for linear Schr{ö}dinger equations with non-trivial compatibility conditions

Joackim Bernier·Ramona Häberli·Gilles Vilmart
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Abstract

Splitting methods are a natural choice for the numerical time integration of partial differential equations, and arbitrary high order splitting schemes exist for Schr{ö}dinger equations with periodic boundary conditions. However, in the presence of non-periodic boundary conditions, we show that they suffer in general from an order reduction, even for smooth initial conditions. The reason for such order reduction phenomena are so-called compatibility conditions, which are not preserved by classical splitting schemes. In this paper, we introduce a family of modified splitting methods for one-dimensional linear Schr{ö}dinger equations with homogeneous Dirichlet boundary conditions, which achieve an arbitrary high order, and do not suffer from any order reduction. This is illustrated with a fourth order splitting scheme considering initial conditions with various regularity properties.

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Joackim Bernier, Ramona Häberli, Gilles Vilmart. 2026-07-06. Arbitrary high order splitting methods for linear Schr{ö}dinger equations with non-trivial compatibility conditions. https://arxiv.org/abs/2607.04835

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