HeTDSE: GPU based program to solve full-dimensional-time-dependent Schr\"{o}dinger equation for two-electron Helium subjected to strong laser fields

TL;DR

HeTDSE is a GPU-accelerated Fortran program that efficiently solves the full-dimensional two-electron time-dependent Schrödinger equation for helium in strong laser fields, enabling advanced electronic dynamics studies.

Contribution

The paper introduces HeTDSE, a GPU-based openACC Fortran program that significantly accelerates solving the full-dimensional two-electron TDSE for helium without code modification.

Findings

HeTDSE running on NVIDIA Kepler K20 GPU outperforms CPU by a factor of 147.

The program effectively models non-perturbative electronic dynamics in helium.

Use of B-Spline basis and spherical harmonics facilitates accurate wavefunction representation.

Abstract

We present a GPU based openACC fortran program named HeTDSE, which provides an efficient way to investigate the non-perturbative electronic dynamics of helium subjected to a strong laser pulse by solving full-dimensional two-electron time dependent Schr\"{o}dinger equation (TDSE). OpenACC is a directive-based programming model for accelerators without modifying the underlying CPU code itself. HeTDSE uses B-Spline basis sets expansion method to construct the radial part of the wavefunction, and the spherical harmonic functions is used to express for the angular part. Adams algorithm is employed for the time propagation. Our example shows HeTDSE running on an NVIDIA Kepler K20 GPU can outperform the one on an Intel E5-2640 single CPU core by a factor of 147.