A real-time TDDFT scheme for strong-field interaction in Cartesian coordinate grid

TL;DR

This paper introduces a real-time TDDFT method using an adiabatic eigenstate subspace and Cartesian grid, enabling efficient simulation of strong-field interactions with demonstrated accuracy in dipole and harmonic spectra.

Contribution

It presents a novel RT-TDDFT scheme based on AES and split operator technique, with direct Cartesian grid computation, improving efficiency and internal consistency.

Findings

Accurately computed TD dipole moments and harmonic spectra.

Validated the scheme against theoretical results.

Demonstrated internal consistency and feasibility.

Abstract

In this communication, we present a new approach towards RT-TDDFT through time-dependent KS equations based on an \emph{adiabatic eigenstate subspace} (AES) procedure. It introduces a second-order split operator technique in energy representation to implement the approximate TD propagator in AES. Most of the elements in TDKS matrix are directly computed in Cartesian coordinate grid (CCG). To demonstrate the internal consistency of our proposed scheme, we computed the TD dipole moment and high harmonic generation spectra using an adiabatic local density approximation. The comparison with available theoretical results ensures the feasibility of this proposed route.