Spin-resolved correlations and ground state of a three-dimensional electron gas: Spin-polarization effects

Abstract

We have studied the spin-resolved correlations in a three-dimensional electron gas having arbitrary spin polarization $\ensuremath{\zeta}$ by using the static and dynamical versions of the self-consistent mean-field approximation of Singwi, Tosi, Land, and Sj\olander, the so-called STLS and qSTLS approaches, respectively. The spin-resolved pair-correlation functions and corresponding correlation energies, static density and spin susceptibilities, and ground-state energy are calculated over a wide range of electron number density and selected $\ensuremath{\zeta}$. Wherever available, our results are compared directly with the recent quantum Monte Carlo studies of Ortiz et al. and Zong et al. The qSTLS approach is found to be in better agreement with the simulation data. As an interesting result, it is found that both the qSTLS and STLS methods underestimate the parallel spin-correlation energy while the antiparallel spin contribution is overestimated to the extent that the total correlation energy is in excellent agreement with the simulation data. Furthermore, a direct comparison among the results of ground-state energy at different $\ensuremath{\zeta}$ reveals, in qualitative agreement with the simulation studies, the existence of a continuous spin-polarization transition on decreasing electron density.