A split-step finite element method for the space-fractional Schrödinger equation in two dimensions

Sci Rep. 2024 Oct 16;14(1):24257. doi: 10.1038/s41598-024-75547-2.

Abstract

In this article, we propose a split-step finite element method (FEM) for the two-dimensional nonlinear Schrödinger equation (NLS) with Riesz fractional derivatives in space. The space-fractional NLS is first spatially discretized by finite element scheme and the semi-discrete variational scheme is obtained. We prove that it maintains the mass and energy conservation laws. Then, we establish a fully discrete split-step finite element scheme for the considered problem, which avoids the iteration at each time layer, thereby significantly reducing computational cost. The discrete mass conservation property and error estimate of this split-step finite element scheme is derived. Finally, illustrative tests and the numerical simulation of dynamic of wave solutions are included to confirm its effectiveness and capability.

Keywords: Error estimate; Finite element scheme; Space-fractional Schrödinger equation; Split-step scheme.