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Pair-distribution functions of the two-dimensional electron gas

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

Based on its known exact properties and a new set of extensive fixed-node reptation quantum Monte Carlo simulations (both with and without backflow correlations, which in this case turn out to yield negligible improvements), we propose a new analytical representation of (i) the spin-summed pair-distribution function and (ii) the spin-resolved potential energy of the ideal two-dimensional interacting electron gas for a wide range of electron densities and spin polarization, plus (iii) the spin-resolved pair-distribution function of the unpolarized gas. These formulae provide an accurate reference for quantities previously not available in analytic form, and may be relevant to semiconductor heterostructures, metal-insulator transitions and quantum dots both directly, in terms of phase diagram and spin susceptibility, and indirectly, as key ingredients for the construction of new two-dimensional spin density functionals, beyond the local approximation.

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Paola Gori-Giorgi, Saverio Moroni, Giovanni B. Bachelet. 2004-03-10. Pair-distribution functions of the two-dimensional electron gas. https://doi.org/10.1103/physrevb.70.115102

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