English

Time-integration of Gaussian variational approximation for the magnetic Schr\"odinger equation

Numerical Analysis 2025-04-07 v1 Numerical Analysis

Abstract

In the present paper we consider the semiclassical magnetic Schr\"odinger equation, which describes the dynamics of charged particles under the influence of a electro-magnetic field. The solution of the time-dependent Schr\"odinger equation is approximated by a single Gaussian wave packet via the time-dependent Dirac--Frenkel variational principle. For the approximation we use ordinary differential equations of motion for the parameters of the variational solution and extend the second-order Boris algorithm for classical mechanics to the quantum mechanical case. In addition, we propose a modified version of the classical fourth order Runge--Kutta method. Numerical experiments explore parameter convergence and geometric properties. Moreover, we benchmark against the analytical solution of the Penning trap.

Keywords

Cite

@article{arxiv.2504.03407,
  title  = {Time-integration of Gaussian variational approximation for the magnetic Schr\"odinger equation},
  author = {Malik Scheifinger and Kurt Busch and Marlis Hochbruck and Caroline Lasser},
  journal= {arXiv preprint arXiv:2504.03407},
  year   = {2025}
}