Semi-local density functional for the exchange-correlation energy of electrons in two dimensions

TL;DR

This paper introduces a new density functional tailored for two-dimensional electron systems, combining gradient-based exchange with a local correlation approach, achieving high accuracy in total energy calculations for quantum dots.

Contribution

The paper develops a semi-local density functional specifically designed for 2D electrons, integrating recent gradient approximations and a Gaussian-based correlation scheme.

Findings

Accurately predicts total energies of quantum dots

Outperforms previous functionals in benchmark tests

Efficient for practical calculations in 2D systems

Abstract

We present a practical and accurate density functional for the exchange-correlation energy of electrons in two dimensions. The exchange part is based on a recent two-dimensional generalized-gradient approximation derived by considering the limits of small and large density gradients. The fully local correlation part is constructed following the Colle-Salvetti scheme and a Gaussian approximation for the pair density. The combination of these expressions is shown to provide an efficient density functional to calculate the total energies of two-dimensional electron systems such as semiconductor quantum dots. Excellent performance of the functional with respect to numerically exact reference data for quantum dots is demonstrated.