Nonequilibrium properties of strongly correlated artificial atoms - a Green's functions approach

TL;DR

This paper develops a nonequilibrium Green's functions approach to study the time-dependent properties of strongly correlated artificial atoms, confirming the preservation of the Kohn mode under certain theoretical approximations.

Contribution

It introduces a NEGF method for inhomogeneous, strongly correlated artificial atoms and demonstrates its effectiveness in analyzing their dynamic properties.

Findings

Kohn mode is preserved in the studied regime.

The NEGF approach accurately captures time-dependent behaviors.

Conserving approximations like Hartree-Fock confirm mode preservation.

Abstract

A nonequilibrium Green's functions (NEGF) approach for spatially inhomogeneous, strongly correlated artificial atoms is presented and applied to compute the time-dependent properties while starting from a (correlated) initial few-electron state at finite temperatures. In the regime of moderate to strong coupling, we consider the Kohn mode of a three-electron system in a parabolic confinement excited by a short pulsed classical laser field treated in dipole approximation. In particular, we numerically confirm that this mode is preserved within a conserving (e.g. Hartree-Fock or second Born) theory.