Correlation energy and spin polarization in the 2D electron gas.
The ground-state energy of the two-dimensional uniform electron gas has been calculated with a fixed-node diffusion Monte Carlo method, 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 our 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.
Attaccalite
Claudio
C
INFM Center for Statistical Mechanics and Complexity and Dipartimento di Fisica, Università di Roma La Sapienza, Piazzale A. Moro 2, 00185 Rome, Italy.
Moroni
Saverio
S
Gori-Giorgi
Paola
P
Bachelet
Giovanni B
GB