# Mass- and energy-conserved numerical schemes for nonlinear Schr\"odinger equations

## TL;DR

This paper introduces new mass- and energy-conserving numerical schemes for nonlinear Schrödinger equations, with analyses and efficient solvers, demonstrating their accuracy and ability to capture blow-up phenomena.

## Contribution

It presents a family of novel time-stepping schemes that conserve mass and energy, along with error analysis and efficient solvers, for nonlinear Schrödinger equations.

## Key findings

- Schemes conserve mass and energy accurately.
- Numerical experiments confirm convergence.
- Methods effectively capture blow-up phenomena.

## Abstract

In this paper, we propose a family of time-stepping schemes for approximating general nonlinear Schr\"odinger equations. The proposed schemes all satisfy both mass conservation and energy conservation. Truncation and dispersion error analyses are provided for each proposed scheme. Efficient fixed-point iterative solvers are also constructed to solve the resulting nonlinear discrete problems. As a byproduct, an efficient one-step implementation of the BDF schemes is obtained as well. Extensive numerical experiments are presented to demonstrate the convergence and the capability of capturing the blow-up phenomenon of the proposed schemes.