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Correlation energy and spin polarization in the 2D electron gas

Claudio Attaccalite·Saverio Moroni·Paola Gori-Giorgi·Giovanni B. Bachelet
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Abstract

The ground state energy of the two--dimensional uniform electron gas has been calculated with fixed--node diffusion Monte Carlo, including backflow correlations, for a wide range of electron densities as a function of spin polarization. We give a simple analytic representation of the correlation energy which fits the density and polarization dependence of the simulation data and includes several known high- and low-density limits. This parametrization provides a reliable local spin density energy functional for two-dimensional systems and an estimate for the spin susceptibility. Within the proposed model for the correlation energy, a weakly first--order polarization transition occurs shortly before Wigner crystallization as the density is lowered.

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Claudio Attaccalite, Saverio Moroni, Paola Gori-Giorgi, Giovanni B. Bachelet. 2003-09-11. Correlation energy and spin polarization in the 2D electron gas. https://doi.org/10.1103/physrevlett.88.256601

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