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arXiv · 1812.00588

Functional-renormalization-group aided density-functional analysis for the correlation energy of the two-dimensional homogeneous electron gas

Takeru Yokota·Tomoya Naito
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Abstract

The functional-renormalization-group aided density-functional theory (FRG-DFT) is applied to the two-dimensional homogeneous electron gas (2DHEG). The correlation energy of the 2DHEG is derived as a function of the Wigner-Seitz radius $ r_{\rm s} $ directly. We find that our correlation energy completely reproduces the exact behavior at the high-density limit. For finite density, the result of FRG-DFT shows good agreement with the Monte Carlo (MC) results in the high-density region, although the discrepancy between FRG-DFT and MC results becomes larger as the system becomes more dilute. Our study is the first example in which the FRG-DFT is applied to more-than-one-dimensional models, and shows that the FRG-DFT is a feasible and promising method even for the analysis of realistic models for quantum many-body systems.

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Takeru Yokota, Tomoya Naito. 2018-12-03. Functional-renormalization-group aided density-functional analysis for the correlation energy of the two-dimensional homogeneous electron gas. https://doi.org/10.1103/physrevb.99.115106

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