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Spin and temperature dependent study of exchange and correlation in thick two-dimensional electron layers

M. W. C. Dharma-wardana
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Abstract

The exchange and correlation $E_{xc}$ of strongly correlated electrons in 2D layers of finite width are studied as a function of the density parameter $r_s$, spin-polarization $ζ$ and the temperature $T$. We explicitly treat strong-correlation effects via pair-distribution functions, and introduce an equivalent constant-density approximation (CDA) applicable to all the inhomogeneous densities encountered here. The width $w$ defined via the CDA provides a length scale defining the $z$-extension of the quasi-2D layer resident in the $x$-$y$ plane. The correlation energy $E_c$ of the quasi-2D system is presented as an interpolation between a 1D gas of electron-rods (for $w/r_s>1$) coupled via a log(r) interaction, and a 3D Coulomb fluid closely approximated from the known {\it three-dimensional} correlation energy when $w/r_s$ is small. Results for the $E_{xc}(r_s,ζ,T)$, the transition to a spin-polarized phase, the effective mass $m^*$, the Landé $g$-factor etc., are reported here.

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M. W. C. Dharma-wardana. 2005-06-30. Spin and temperature dependent study of exchange and correlation in thick two-dimensional electron layers. https://doi.org/10.1103/physrevb.72.125339

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