Leading gradient correction to the kinetic energy for two-dimensional fermion gases

Abstract

Density functional theory (DFT) is notorious for the absence of gradient corrections to the two-dimensional (2D) Thomas-Fermi kinetic-energy functional; it is widely accepted that the 2D analog of the 3D von Weizsäcker correction vanishes, together with all higher-order corrections. Contrary to this long-held belief, we show that the leading correction to the kinetic energy does not vanish, is unambiguous, and contributes perturbatively to the total energy. This insight emerges naturally in a simple extension of standard DFT, which has the effective potential energy as a functional variable on equal footing with the single-particle density.

6 pages, 2 figures

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Cited by in corpus (10)

• Gradient correction and Bohm potential for 2D and 1D electron gases at a finite temperature
• Systematic corrections to the Thomas-Fermi approximation without a gradient expansion
• Airy-averaged gradient corrections for two-dimensional fermion gases
• First-principles quantum corrections for carrier correlations in double-layer two-dimensional heterostructures
• Self-consistent assessment of Englert-Schwinger model on atomic properties
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• Phase Transitions of Repulsive Two-Component Fermi Gases in Two Dimensions
• Preserving the Hermiticity of the One-Body Density Matrix for a Non-Interacting Fermi Gas