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arXiv · 1907.02782

A note on optimal $H^1$-error estimates for Crank-Nicolson approximations to the nonlinear Schrödinger equation

Patrick Henning·Johan Wärnegård
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Abstract

In this paper we consider a mass- and energy--conserving Crank-Nicolson time discretization for a general class of nonlinear Schrödinger equations. This scheme, which enjoys popularity in the physics community due to its conservation properties, was already subject to several analytical and numerical studies. However, a proof of optimal $L^{\infty}(H^1)$-error estimates is still open, both in the semi-discrete Hilbert space setting, as well as in fully-discrete finite element settings. This paper aims at closing this gap in the literature. We also suggest a fixed point iteration to solve the arising nonlinear system of equations that makes the method easy to implement and efficient. This is illustrated by numerical experiments.

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Patrick Henning, Johan Wärnegård. 2020-07-07. A note on optimal $H^1$-error estimates for Crank-Nicolson approximations to the nonlinear Schrödinger equation. https://arxiv.org/abs/1907.02782

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